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carpenter's square
instigation; suggestion; manipulation; (someone's) doing
metal wire with a prop animal (e.g. butterfly, bird) attached to the end
rod used to control the arm of a puppet (in bunraku)
差し金で直角を確認した。
I checked the right angle with a carpenter's square.
差し金は木工で必須の道具だ。
A carpenter's square is essential for woodworking.
差し金を使って線を引いた。
I drew a line using a carpenter's square.