約
ヤク, つづ.まる, つづ.める, つづま.やか
promise, approximately, shrink
JLPT3 G4 S9 F94
As per 勺# (rise and become evident) + 糸 thread → *tie* a knot in a cord (as a sign of a pledge) → *promise*; *conspicuous mark* → *brief*; *summary* (← reduce in making compact; compare 要) → *approximately* (← summary approximating a full report in providing only the gist).
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