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something to rely on; aid; clue; way; means
someone to rely on; relative
reminder; memento
「便」 has other readings with different meanings.
この辺りは交通の便がいいよね。
This area has good transportation.
便がいい場所に引っ越したいな。
I want to move to a convenient place.
便の悪い所に住んでいるんだ。
I live in an inconvenient place.