Abortive

defective, barren.

Abrupt

appearing as if suddenly terminated or broken off.

Accrescent

persistent and increasing in size.

Accrete

having contiguous parts or organs naturally grafted together.

Acerose

linear and sharp-pointed, as in the leaves of the fir-tribe.

Achene

a dry, hard, single-seeded indehiscent fruit, with the pericarp inferior, and consequently invested by the calyx, as in the seeds of compound flowers.

Achlamydeous

without any distinct perianth, as in the willows.

Acicular

of slender form, like a needle.

Acotyledonous

wanting cotyledons.

A culeate

sharply pointed or prickly.

Acuminate

ending in a long, taper point.

Acute

when the extremities present an angle less than a right angle.

Adherent

having parts originally or normally distinct, united or grafted together.

Adnate

attached throughout the long length, as in the case of anthers when their lobes are attached throughout their whole length to the filament, or of stipules when they adhere to the peduncles, etc.

Adpressed

having one part lying close to another throughout its length, as hairs to the surface of a leaf.

Aggregated

having similar but distinct parts crowded together.

Albumen

a substance of a farinaceous, oily, or horny consistency, found in many seeds, surrounding the embryo wholly or in part.

Alternate

having the parts or organs so placed, that the one is not directly before or over-against the other.

Amplexicaul

having the peduncle, leaf, or stipule dilated at the base, and extended partially round the stem, so as to clasp it.

Angular

having a determinate number of angles.

Annual

applied to those plants which produce seed and die in the same year in which they germinate.

Anther

that portion of the stamen which contains the pollen, most frequently formed of two distinct cells, and generally attached towards the summit of a filament.

Antheriferous

bearing or supporting the anthers.

Apetalous

applied to flowers which are destitute of true corolla.

Apex

the opposite extremity of any organ to that by which it is attached, which is considered its base.

Apiculate

terminating in a sharp but short point.

Apocarpous

having the carpels quite free from adhesion, as in the Buttercup.

Appendage

a part superadded to another, as the leaves to the stem.

Appressed

closely applied to some other part throughout its whole length, as the pubescence on some leaves and branches.

Aquatic

living or growing in water.

Aril

Arillus, an expansion of the placenta, rising around certain seeds in the form of an integument, generally more or less fleshy, as in the genus Euonymus.