not one thread loose (idiom); strictly according to the rules; meticul
一 · 1 strokes
A single horizontal stroke, representing the number one.
丝 · 5 strokes
Simplified form of 絲. Duplication of 纟 (silk).
不 · 4 strokes
Pictograph of sepals of a flower. The modern meaning "no" is a phonetic loan.
苟 · 8 strokes
Phonosemantic compound. 艹 represents the meaning and 句 represents the sound.
他做事总是一丝不苟。
not one thread loose (idiom); strictly according to the rules; meticulous; not one hair out of place