- alpha_tocopheral
- alvin ailey
- arms
- atom bomb
- aerosol bomb
- atomic bomb
- at the same time
- all at once
- a versatile person
- a denominator
- a master of all trades
- a suffix imparting the meaning of one who or that which takes away
- apidae
- apios
- annualry
- annualized
- Actias luna
- Antheraea polyphemus
- Aranea
- Antheraea pernyi
- Aspidiotus
- Adelges
- Actias
- Argyrotaenia
- Alsophila
- Anasa
- Acanthoscelides
- Anthidium
- Anabrus
- Amphibolips
- Anthonomus
- Andricus
- Apis
- Atticus
- Antheraea
- Adalia
- Aleyrodes
- Argiope
- Araneus
- Apatura
- Anomala
- Astacus
- Acherontia
- Armadillidium
- Artemia
- Aphis
- Argynnis
- Anagasta
- Arilus
- Acheta