abaxial
Facing away from the stem of a plant (especially denoting the lower surface of a leaf).
acerose
Narrow with a sharp stiff point.
achene
A simple, dry, one–seeded (one–celled) fruit.
acicular
Needle-shaped.
acidic
Having a low pH, opposite of basic or alkaline.
acroscopic
Pointing towards, or on the side of, the apex.
acuminate
Gradually tapered to a point. Sharply pointed.
acute
Pointed or sharp, tapering to a point with straight sides.
adnate
Fusion of unlike parts, e.g. stamens fused to petals.
adventive
A plant that grows in the wild in New Zealand but which was introduced to the country by humans.
agglutinated
Stuck together.
allelopath
An organism that releases compounds that are toxic to other species.
allelopathy
The release by an organism of compounds that are toxic to other species.
alternate
Attached singly at each node but changing from one side of a stem to the other.
alveolate
Honeycombed with ridged partitions.
amplexicaul
Clasping or surrounding the stem.
anamorph
Asexual fruiting stage, usually of an ascomycete fungus.
anastomosing
Rejoining after branching, as in some leaf veins.
annual
A plant that completes its complete life cycle within the space of a year.
annual evergreen
Plants that lose their over-wintering leaves rapidly in the first half of the growing season. Annual evergreens never present a leafless appearance, but are closer in a functional sense to a deciduous plant than they are to multi-annual evergreens.
annulus
Line of thickened cells that governs the release of spores from a sporangium.
anterior
Towards the front.
anther
The pollen-bearing portion of the stamen.
antheridium
Male reproductive organ formed on the prothallus of a fern.
anthesis
Flowering period from when the bud opens
apex
Tip; the point furthest from the point of attachment.
apices
Plural of apex. Tip, the point furthest from the point of attachment.
apiculate
Bearing a short slender and flexible point.
apiculus
A small, slender point.
apomixis
A form of reproduction whereby seed is formed without the usual mode of sexual fusion.
appressed
Pressed against another organ or surface.
aquatic
Growing, or living in, or frequenting water. Applied to plants and animals and their habitats. Opposite of terrestrial (land living).
archegonium
Female reproductive organ of a fern formed on the prothallus.
arcuate
Curved into an arch.
aril
An often fleshy appendage on the outside of a seed.
artificial thinning
Selectively removing vegetation to create gaps to facilitate natural invasion of native plants, or to plant later successional plants.
ascending
Growing obliquely upward.
asexual
Vegetative reproduction, lacking sexual involvement by sperm or egg cells.
auricle
A small, ear-shaped appendage.
auriculate
Bearing a small, ear-shaped appendage.
autogamous
Self-fertilising flowers.
awn
A stiff or bristle like projection often from the tip or back of an organ.
axil
The upper angle between the leaf and the stem.
axis
The longitudinal supporting structure around which organs are borne, e.g., a stem bearing leaves.
autotrophic
Of or relating to organisms (as green plants) that can make complex organic nutritive compounds from simple inorganic sources by photosynthesis.
attenuate
Narrowing gradually.
