1. (noun)basis, base, foundation, fundament, groundwork, cornerstone the fundamental assumptions from which something is begun or developed or calculated or explained
"the whole argument rested on a basis of conjecture"
2. (noun)foundation, base, fundament, foot, groundwork, substructure, understructure lowest support of a structure "it was built on a base of solid rock"; "he stood at the foot of the tower"
Definition of 'groundwork'
