Keyword
What KeyWord is found in the definitions of each of the following?

173 greenhead, eiderdown, bigarade, gadwall, merganser (4 letters)
174 culm, slack, buran, siderosis, pulverulent (4 letters)
175 tinnitus, tragus, auriform, periotic, otoscope (3 letters)
176 outre, barmy, oddball, crotchety, Icarus (the asteroid) (9 letters)
177 pinger, reverberate, tormentor, reply, resound (4 letters)
178 glair, ovate, souffle, oology, vitelline (3 letters)
179 evict, expectorate, squirt, chuck, oust (5 letters)
180 ulna, cubit, humerus, olecranon, funny bone (5 letters)
181 musth, howdah, proboscidian, trumpet, rogue (8 letters)
182 ecstacy, tailspin, affective, impassive, sentiment (7 letters)

Answers: 173. duck, 174. dust, 175. ear, 176. eccentric, 177. echo, 178. egg, 179. eject, 180. elbow, 181. elephant, 182. emotion,

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