1. Characterized by the interdependence of living organisms in an environment
   - ecological 
2. Of or relating to the science of ecology
   - ecological, bionomical, bionomic

See also: ecology

• Arkansan
• Arkansas
• Arkansas kingbird
• Arkansas River
• Arkansawyer
• arkose
• arles
• Arlington
• arm
• arm bone
• arm candy
• arm exercise
• arm in arm
• arm pad
• arm's length
• arm-twisting
• armada
• Armadillidiidae
• Armadillidium
• armadillo
• Armageddon
• Armagnac
• armament
• armamentarium
• Armand Jean du Plessis