bombast: [16] Bombast originally meant ‘cotton-wool’, especially as used for stuffing or padding clothes, upholstery, etc; hence, before the end of the 16th century, it had been transferred metaphorically to ‘pompous or turgid language’. The ultimate source of the word was Greek bómbux ‘silk, silkworm’, which came into English via Latin bombyx, bombax (source also of English bombazine [16]) and Old French bombace. The earliest English form was bombace, but it soon developed an additional final -t. => bombazine
