[1] : The Collaborative International Dictionary of English v.0.48

catkin \cat"kin\ ka^t"ki^n, n. cat + -kin. bot.
   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
see also:
ament 

[2] : WordNet (r) 2.0

catkin
     n : a cylindrical spikelike inflorescence syn: ament
see also:
ament 

Catkin >> C Words
Catkin, definition of term: Catkin
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