metal reinforcement; reinforcing bar; stiffener
Refers to a metal bar, rod, or wire used to strengthen concrete, frameworks, or structures. Also used figuratively to describe a person of firm principles or strong will.
The pillars of this building have metal reinforcements inside.
彼は筋金入りの保守派だ。
He is a dyed-in-the-wool conservative.
staunch; hardcore; dyed-in-the-wool · metal reinforcement
Standard kanji spelling; used in both literal and figurative senses.
Compound of 筋 (すじ, 'line, fiber, tendon') and 金 (かね, 'metal'), with rendaku voicing. The figurative sense comes from the idea of a metal core that provides strength and rigidity.