- abies
- ablastous
- abstriction
- abterminal
- acaulescent
- acrospire
- actinotropism
- acutifoliate
- acorn cup
- acorn-shaped
- acrophilous
- acroscopic
- actinocarpous
- acutiflorous
- adpressed
- agrimony
- agminated
- alpenstrine
- althaea
- alyssum
- amanthicolous
- amanthophilous
- amanthophily
- angiogamy
- antherophore
- anthracnose
- anisocarpous
- anisogamy
- anantherous
- anther
- antherlobe
- anthocarpous
- anthodium
- andric
- androclinium
- androgamete
- androgamic
- androgamy
- androphore
- androphyll
- androspore
- antherless
- apogyny
- arborvitae
- artemisia
- asciferous
- asporous
- appressed
- aquilegia
- arthrospore