means The folded flap of fabric on each side of a coat or jacket's front, just below the collar, where it turns back against the chest.

from A diminutive of 'lapel' from English 'lap' — the loose, hanging part of a garment that folds over — with the '-el' ending marking it as a little fold. The word surfaced in the 18th century as coats began turning their fronts back to reveal the lining, a fold that hardened over time into the fixed, pressed shape we know now.