a very small hole or opening, especially in a wall （尤指墙上的）小孔，缝隙，裂缝 Word Originlate Middle English: from Old French crane ‘notched’, from cran, from popular Latin crena ‘notch’.
Idioms
every nook and cranny
(also Indian English every nook and corner)
- (informal)
every part of a place; every aspect of a situation 到处；各个方面 The wind blew into every nook and cranny. 风吹进了每个角落。 She always explored every nook and cranny of a business deal. 她总是探索商业交易的每一个细节。