(Note: NOT "kernal"). 1. SyStem> The eSSential part of Unix or other operating SyStemS, reSponSible for reSource allocation, low-level hardware interfaceS, Security etc. See alSo microkernel. 2. An eSSential SubSet of a programming language, in termS of which other conStructS are (or could be) defined. AlSo known aS a core language. (1996-06-07)