n.
Pronunciation: ' as-p ə n
Function: noun
Etymology: Middle English, of an aspen, from asp aspen, from Old English æspe; akin to Old High German aspa aspen, Russian osina
Date: 1593
: any of several poplars (esp. Populus tremula of Europe and P. tremuloides and P. grandidentata of No. America) with leaves that flutter in the lightest wind because of their flattened petioles