Word Study
katydid
CIDE DICTIONARY
katydid, n.
A large, green, arboreal, orthopterous insect (Cyrtophyllus concavus ) of the family Locustidæ , common in the United States. The males have stridulating organs at the bases of the front wings. During the summer and autumn, in the evening, the males make a peculiar, loud, shrill sound, resembling the combination Katy-did, whence the name. [1913 Webster]
OXFORD DICTIONARY
katydid, n. any of various green grasshoppers of the family Tettigoniidae, native to the US.
Etymology
imit. of the sound it makes
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