1. (biology) the growth, development and other responses of plants and animals to the length of day during the year

Derived forms: photoperiodisms

Encyclopedia: Photoperiodism

• at any rate
• at arm's length
• at bay
• at best
• at bottom
• at close range
• at fault
• at first
• at first blush
• at first glance
• at first hand
• at first sight
• at hand
• at heart
• at home
• at issue
• at large
• at last
• at least
• at leisure
• at length
• at loggerheads
• at long last
• at most
• at odds