背広
せびろ · sebiro · JLPT N5 · noun
suit
👔 背広 = back + wide; sebiro may echo Savile Row, London's tailoring street
The kanji are ateji: 背 (back) + 広 (wide), fitting a jacket cut broad across the back. The sound sebiro is often traced to Savile Row, the London street famous for tailors, or to the English word civil, as in civil clothes.
背 — north 北 (phonetic) + flesh 月/肉
Originally a phono-semantic compound: 月 (a form of 肉, 'flesh/body') gives the meaning 'back of the body,' while 北 supplies the sound. Interestingly, 北 itself depicted two people back-to-back and once meant 'back'; when it was borrowed for 'north,' 背 was created with the flesh radical to keep the original sense.