Green’s Dictionary of Slang

double-barrel n.1

[SE double-barrel, a double-barrelled gun]

field-glasses, opera-glasses.

Show quotations
H.D.Traill Sat. Songs 61: Intently as the master plies O’er all the stage his double-barrel / That Eightyer mute had fixed his eyes / Upon his honoured guest’s apparel [F&H].