Merriam-Webster's Collegiate® Dictionary, 11th Edition
GIMMICK
I. noun
Etymology: origin unknown
Date: 1922
1. a mechanical device for secretly and dishonestly controlling gambling apparatus, an ingenious or novel mechanical device ; gadget ,
2. an important feature that is not immediately apparent ; catch , an ingenious and usually new scheme or angle, a trick or device used to attract business or attention , gimmicky adjective
II. transitive verb
Date: 1922
to alter or influence by means of a gimmick, to provide with a gimmick