- aldol reaction
- Acanthophis
- Ancistrodon
- Anolis
- Agkistrodon
- Anguis
- Aspidelaps
- Aspis
- Amphisbaenia
- Amblyrhynchus
- also_ran
- asa dulcis
- atriplex hortensis
- anas querquedula
- aioli sauce
- american crab apple
- aioli
- almandite
- almandine
- association theory
- associationism
- Arrhenius theory of dissociation
- atomism
- abasia
- aggravating
- an aggregate of seven
- armed combat
- a religious preach
- a ray of sunshine
- amygdala
- afferent neuron
- areaway
- Aulostomus maculatus
- acanthopterygian
- Acipenser huso
- agapanthus africanus
- air thermometer
- activex
- anzio
- aoembryonic pole
- athletic type
- architeuthis
- an affair
- a division of a book_section
- a mendicant's tattered dress
- a good samaratian
- a hell of a
- a fat lot
- a heavy sword with wide knife
- antirabic