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one side; one party; the other side; the other party
one (of a pair); the other (one); the mate; the fellow
靴下の片方が見つからない。
I can't find one of my socks.
片方の手で荷物を持っていた。
I was holding the luggage in one hand.
片方だけ意見を聞いても公平ではない。
It is not fair to hear only one side's opinion.