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armpit; under one's arm; side; flank
beside; close to; near; by
aside; to the side; away; out of the way
off-track; off-topic
deuteragonist; supporting role
second verse (in a linked series of poems)
暑くて腋に汗をかいてしまった。
It was hot and I ended up sweating under my arms.
大きな荷物を腋に抱えて走った。
I ran with a big package tucked under my arm.
腋の下が痛いので病院に行った。
My armpit hurt, so I went to the hospital.