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very hungry; starving; famished
bowing repeatedly; kowtowing; bowing and scraping; being obsequious; being servile
denting; buckling; giving (in)
お腹がぺこぺこで今すぐ何か食べたい。
My stomach is empty and I want to eat something right now.
彼は上司にぺこぺこ頭を下げていた。
He was bowing repeatedly to his boss.
ぺこぺこするのはあまり好きではない。
I don't really like being overly deferential.