筋がいい

• Reading: すじがいい
• Romaji: suji ga ii
• Kanji breakdown: 筋 (suji) — muscle, sinew, talent, logic
• Pronunciation: /sɯ.dʑi.ɡa.iː/

Meaning

Having an aptitude for something; having natural talent; showing good form or instinct.

An idiomatic expression where 筋 (suji) means 'sinew/line' but metaphorically refers to one's natural talent or instinct. 筋がいい describes someone who picks things up quickly or shows natural ability. Common in sports, martial arts, music, and other skill-based activities. The opposite is 筋が悪い (lacking aptitude). Can also describe ideas: その提案は筋がいい (that proposal has good logic).

Examples

1. あの子は筋がいいからすぐ上達するだろう。 That kid has a natural talent, so they'll probably improve quickly.
2. ピアノを始めたばかりなのに筋がいいと褒められた。 Even though I had just started piano, I was told I had good instincts.
3. この仕事は筋がいい人ならすぐ覚えられる。 If you have a knack for it, you can pick up this job quickly.

Usage Guide

Context: sports, learning, coaching

Tone: encouraging

Origin & History

From 筋 (suji, sinew/muscle fibre), which metaphorically extends to mean 'line of reasoning,' 'talent,' or 'natural disposition.' Good 筋 implies well-aligned muscles — the body naturally suited for a task. This physical metaphor expanded to encompass intellectual and artistic aptitude.

Cultural Context

Era: Early Modern

Generation: All ages

Social background: Universal