Word Study
catkin
CIDE DICTIONARY
catkin, n. [Cat + -kin.].
An ament; a species of inflorescence, consisting of a slender axis with many unisexual apetalous flowers along its sides, as in the willow and poplar, and (as to the staminate flowers) in the chestnut, oak, hickory, etc. -- so called from its resemblance to a cat's tail. See Illust. of Ament. [1913 Webster]
OXFORD DICTIONARY
catkin, n. a spike of usu. downy or silky male or female flowers hanging from a willow, hazel, etc.
Etymology
obs. Du. katteken kitten
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