This glossary explains botanical and related terminology that you may come across in wildflower books and in plant science papers.
| Term |
Explanation |
| Achene |
One-seeded, non-splitting dry fruit |
| Acidophile |
Preferring to grow on acid soils |
| Achlorophyllose |
Without chlorophyll, a green pigment, and therefore unable to photosynthesise |
| Actinomorphic |
Radially symmetrical or having more than one plane of symmetry |
| Aculeate |
Armed with sharp prickles or thorns |
| Acute |
Sharply pointed (referring to a leaf, for example) |
| Adventitious |
Roots and buds that appear on a stem in abnormal places |
| Albinism |
A complete lack of pigmentation |
| Albino |
Plant lacking pigmentation |
| Alien |
Plant introduced from outside its natural range |
| Alkaline |
Calcareous or chalky substrates |
| Allele |
One possible form of a gene |
| Allogamy |
Fertilisation by pollen from a flower of the same species |
| Allopatric |
Species in geographical areas that do not overlap |
| Alternate |
Leaves occurring singly on opposite sides of a stem, rather than in pairs |
| Anemophilous |
Pollinated by wind |
| Angiosperm |
Flowering plant whose seeds develop inside an ovary |
| Annual |
A plant that germinates, flowers and dies within 12 months |
| Annular |
Ring-shaped |
| Anther |
A male reproductive organ of a flower that bears pollen |
| Anthocynanins |
Pigments producing red or purple colours |
| Anthoxanthins |
Yellow pigments in plants |
| Aphyllous |
Without leaves |
| Apical |
At the tip |
| Apochromy |
Having abnormal colour |
| Apomixis |
Seed reproduction from unfertilised egg cells |
| Aquatic |
A plant whose natural habitat is water (usually implying inland freshwater habitats) |
| Asymbiotic |
When symbiotic fungi are absent |
| Auricles |
Ear-shaped structures |
| Autogamous |
Self-pollinating |
| Axil |
The angle between a stem and a branch or a leaf |
| Back-cross |
Cross between a hybrid and one of its parents |
| Basal |
Located at the base of an organ, for example a leaf at the base of a stem |
| Bog |
Wet, acidic peat |
| Bosses |
Irregular swellings |
| Bract |
Leaf-like structure often found beneath a flower |
| Bracteole |
Secondary bract at the base of secondary branches of the flower stalk |
| Bulb |
Food storage organ formed by a cluster of fleshy leaf bases |
| Bulbil |
A small bulb sometimes located in the axil of a leaf or bract |
| Calcareous |
Usually refers to limstone rock or chalky soil with a high calcium content |
| Calyx |
The outer whorl of a flower, which is made up of its set of sepals |
| Capsule |
A dry seed pod |
| Carapace |
Hardened shell |
| Carpel |
The female seed-producing unit in a flower, consisting of an ovary connected by a style to a stigma |
| Cilia |
Tiny fleshy hair-like structures |
| Chlorophyll |
Green pigment important in photosynthesis |
| Cladode |
Modified stem that resembles a leaf (for example in Butcher's Broom) |
| Cleistogamous |
Self-pollinating flowers with petals and sepals that never open |
| Clone |
Identical genetic match to a 'parent' |
| Corolla |
Inner whorl of petals of a flower |
| Corona |
Petal-like flaps, often elongated to form a crown-like tube (as for example in a daffodil) |
| Crenate |
Structures with minute scalloped or round-toothed margins |
| Cross-pollination |
Pollination of one flower by pollen from another, usually from a different plant |
| Cyme |
Cluster of flowers with lateral branches each ending in a flower |
| Deciduous |
Sheds leaves or other organs in one limited period during every year (unlike evergreens whose leaves are not all shed at the same time) |
| Decurved |
Curved downwards |
| Deflexed |
Bent sharply downwards |
| Diploid |
Normal state for plant cells - containing two matching sets of chromosomes |
| Disc floret |
A flower in the centre of a flower-head whose petals form a tube |
| Drupe |
Fleshy fruit containing seeds surrounded by a toughened coat (as in plums, peaches etc) |
| Drupelet |
One of a group of connected drupes (as in blackberries etc) |
| Ectomychorrhiza |
Association with fungi where the fungus forms a layer on the outside of the roots of a plant |
| Endomychorrhiza |
Association with fungi where the fungus penetrates the root of a plant |
| Epicalyx |
Second ring of sepal-like organs immediately below the true sepals (calyx) |
| Epichile |
Outer portion of the lip in those orchid genera where the lip is divided into two parts |
| Epidermis |
A 'skin' or surface layer |
| Epiphyte |
A plant that grows on the surface of another but without taking nutrients from it |
| Escape |
Refers to a non-native plant that is cultivated and then becomes established in the wild |
| Esker |
Glacial deposits such as sand and gravel |
| Eutrophication |
Where a habitat becomes over-enriched with nutrients. This happens frequently with rivers or ponds as a result of run-off from farming and is often the cause of native species becoming stifled or destroyed |
| Fall petal |
One of the three outer petals of the iris that droop downwards |
| Family |
Classification unit grouping closely related genera |
| Fen |
Marshes and wetlands sited on alkaline, neutral or only very slightly acid soil, often but not always beside lakes |
| Floret |
One of the small flowers contained in a flower-head |
| Filiform |
Thread-like |
| Flower head |
A cluster of florets or flowers |
| Garrigue/Garigue |
Habitat with low-growing shrubs with wide gaps in between them. Common in the Mediterranean region |
| Geitonogamy |
Fertilised by pollen from a flower on the same plant |
| Genus |
Classification unit grouping together closely related species (Pl. genera) |
| Gland |
Superficial organ that secretes oils or other substances |
| Glandular hair |
Hair containing a gland |
| Hemiparasitic |
A plant relying partly on the nutrients abstracted from other plants |
| Herbarium |
Collection of dried, pressed plants |
| Herbaceous |
A plant that dies down to ground level at the end of the growing season |
| Hooded |
Developed into a concave shape |
| Hybrid |
Plant originating from cross pollination between two different species |
| Hybrid swarm |
Population of plants where the barriers between two species have broken down leading to hybrids and back crosses interbreeding. The resulting plants exhibit a variety of characteristics from both 'parents' |
| Hybrid vigour |
Where plants of the first generation of hybrids become exceptionally large and robust |
| Hypanthial tube |
Tube formed from by an extension of the receptacle below a flower |
| Hyperchromic |
Having an excessive amount of pigmentation, resulting in more intense colour |
| Hypha |
Fine thread-like structure that makes up the body of a fungus. Pl. hyphae |
| Inflorescence |
A group of flowers arising from one stem |
| Intergeneric hybrid |
A hybrid where the 'parents' are from two different genera |
| Internode |
Stem section between two nodes |
| Introduced |
Brought into an area by human or other means |
| Involucre |
Ring of crowded bracts encircling a flower head |
| Involucral bract |
Bract forming part of an involucre |
| Keel/Keel petal |
Lower fused petals of a pea flower folded to form a hull-like structure |
| Lanceolate |
Oval and narrowing to a pointed tip |
| Latex |
Milky sap |
| Lax |
Loose rather than densely packed (usually applied to the flowers in an inflorescence) |
| Lignify |
To become woody |
| Lip |
A petal that protrudes, forming a lobe. Found in orchids and in flowers of the Mint family |
| Machair |
Confined to the coasts of western Ireland and Scotland, a sandy, lime-rich (usually as the result of crushed shells) habitat usually species-rich |
| Maquis |
An area of densely-packed shrubs up to five metres in height. Common in the Mediterranean region |
| Meadow |
Grassy field which kept for the production of hay and grazed only infrequently |
| Mealy |
A flour-like texture or substance |
| Mericarp |
One-seeded portion of a fruit formed when it splits from the rest of the fruit |
| Monocarpic |
Flowers once and then dies |
| Mutualism |
Relationship between organisms from which all benefit |
| Micorrhizome |
Early stage of seedling development during which it is solely dependent on fungi for nutrients |
| Mycorrhiza |
Relationship between plant and fungus where the fungus will penetrate or form a layer over the roots |
| Mycelium |
Mass of branching filaments that make up the body of a fungus |
| Mycotrophic |
Acquiring nutrients from fungus |
| Native |
Belonging to a region through natural circumstances |
| Naturalised |
Introduced to a region but subsequently forming self-sustaining populations |
| Nectary |
Nectar-secreting gland |
| Node |
Point on a stem where one or more leaves are attached |
| Ovary |
Female reproductive organ containing ovules |
| Ovule |
Organ inside ovary enclosing the embryo sac containing an egg |
| Panicle |
Branched cluster of flowers with stalks |
| Pappus |
Tuft of hair on achenes or other fruits which aids seed dispersal |
| Parasitic |
Entirely dependent for it survival on abstracting nutrients from another plant |
| Pasture |
Grassland that is grazed for part of a year and not cut for hay or silage |
| Pedicel |
Stalk of flower |
| Petals |
Inner whorl of perianth segments - the outer one being the sepals |
| pH |
Measure of acidity or alkalinity based on a logarithmic scale of hydrogen ion concentration, where 0 is most acidic, 7 is neatral, and 14 is most basic (alkaline) |
| Pheromone |
Chemical produced by animal or insect that influences the behaviour of other members of the same species |
| Photosynthesis |
Process of production of food by green plants |
| Phototropic |
Acquisition of food by photosynthesis |
| Pinnate |
Leaflets arranged on two sides of a single stalk |
| Pollen |
Spores with single cell containing male gamete |
| Pollinium |
Mass of pollen transported during pollination |
| Raceme |
Unbranched flower cluster where each flower is stalked |
| Ray/Ray-floret |
Outer, flattened flower of a daisy-type flower head with a large petal extending radially outwards; the inside reagion of the flower head consists of disc florets with much smaller, equal-sized petals |
| Receptacle |
That part of the stem that has flower parts attached to it |
| Recurved |
Bent or curved backwards |
| Reflexed |
Bent down or back |
| Reticulation |
Marked with network of veins |
| Rhizome |
Creeping (usually underground) thickened stem that stores food |
| Runner |
Stem that creeps along the ground and forms roots at periodic intervals that will eventually form separate plants |
| Saprophyte |
Plant feeding on rotten vegetation in the ground |
| Scape |
Leafless stem bearing flowers |
| Secund |
Facing in the same direction |
| Sepal |
Outer row or ring of perianth segments forming the protective covering of a flower bud |
| Septum |
A thin partition or membrane separating the individual seeds within a seed pod or fruit |
| Sessile |
Without a stem |
| Silicula |
Fruit of the cabbage family, often rounded and three times longer than it is broad |
| Simple |
Leaves not divided into leaflets |
| Spadix |
Fleshy spike with unstalked flowers |
| Spathe |
Large hooded bract enclosing a spadix |
| Species |
Classification of a group of similar individuals that breed true in the wild |
| Speculum |
Mirror-like patch found on the petals of some orchids |
| Spike |
Unbranched cluster of flowers that are unstalked |
| Stamen |
Male reproductive organ of a flower |
| Spur |
Hollow pouch, sometimes cylindrical or conical, projecting from a flower and containing nectar |
| Standard/Standard petal |
Upright, upper petal of a pea flower that is larger than the others |
| Stemless |
A plant without an obvious stem but with a flower stalk that arising directly from the ground |
| Stigma |
Part of a flower that receives pollen |
| Stigma ray |
Star-shaped stigma with radiating branches |
| Stipule |
Leaf-like organ at the base of a leaf stalk |
| Stolon |
Stem growing horizontally above or below the ground |
| Style |
The part of the female reproductive organ that joins the ovary to the stigma |
| Subshrub |
Small perennial with woody stems |
| Succulent |
Plant with fleshy leaves |
| Suture |
Seam along which pods or other fruits split open |
| Symbiosis |
Relationship between two or more organisms in which all benefit |
| Tap root |
Strong main root that grows vertically downwards |
| Tepal |
Petals and sepals that cannot be clearly distinguished from each other |
| Trifoliate |
Leaf made up from three distinct leaflets, for example as in clover |
| Tuber |
Food storage organ formed by a swollen underground stem |
| Tubercle |
Small warty protuberance |
| Umbel |
Flat or domed-topped flower cluster with all the stems originating at the same place, as for example in cow parsley |
| Valve |
One of several parts of a fruit that become partially or fully separated |
| Whorl |
Collection of organs that encircle a stem |
| Wing/Wing petal |
Lateral petals of many flowers particularly orchids and pea flowers |
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