nounany of several small falcons, esp the European Falco tinnunculus, that tend to hover against the wind and feed on small mammals on the ground
 Word origin
C15: changed from Old French 
cresserele, from 
cressele rattle, from Vulgar Latin 
crepicella (unattested), from Latin 
crepitāre to crackle, from 
crepāre to rustle