n. — Automotive
a gas station without a service garage (see Image 1).
Type: 1. Origin — The term is extremely rare outside of the country, as shown in Chart 1.
The shortened form, gas bar, is the more common form today. In spoken discourse in urban areas, gas bar does not seem to have much currency. It seems to have appeared in the 1950s (see the 1960 citation with the term in quotation marks) and was apparently formed in analogy to older compounds such as gas boat 'motor boat' and gas-car 'automobile', and their long forms, which are found in DCHP-1 from 1919 and 1934 respectively.
See also COD-2, which marks the term "Cdn", OED-3, s.v. "gas bar", which is marked "Canad.".
See also: gas boat gas-car
- Note that the term is not listed in DCHP-1 and Gage-1, as a very new term at the time, but also not in Gage 5 or ITP Nelson.
Images:

Image 1: A gas bar in Vancouver, BC. Photo: S. Dollinger 
Chart 1: Internet Domain Search, 13 Aug. 2012