Gaster is a German surname. 
The "Dictionary of American Family Names" (2003) suggests that it may be a derivation from "Gast" "guest".
There were 918 entries in the US white pages for this name as of 2013, the largest number (221 entries) in North Carolina. In Germany, there were 95 entries as of 2008.
Notable people with the surname include: 
References.
 ;templatestyles src="Reflist/styles.css" / ;
 ;templatestyles src="Dmbox/styles.css" / ;
 Surname listThis page lists people with the surname Gaster. 