1. Showing sustained enthusiastic action with unflagging vitality
   - indefatigable, tireless, unflagging

See also: energetic

• genus Chaenactis
• genus Chaenomeles
• genus Chaenopsis
• genus Chaetodipterus
• genus Chaetodon
• genus Chalcis
• genus Chalcostigma
• genus Chamaea
• genus Chamaecrista
• genus Chamaecyparis
• genus Chamaecytisus
• genus Chamaedaphne
• genus Chamaeleo
• genus Chamaeleon
• genus Chamaemelum
• genus Chara
• genus Charadrius
• genus Charina
• genus Charronia
• genus Chateura
• genus Chauna
• genus Cheilanthes
• genus Cheiranthus
• genus Chelidonium
• genus Chelifer