1) Assumption 2) Base 3) Basis 4) Cornerstone 5) Foundation 6) Foundation or preparation 7) Fundament 8) Labour 9) Lowest support of a structure 10) Preliminaries 11) Research 12) Spadework 13) Supposal 14) Supposition 1) Base 2) Basis 3) Cause 4) Cornerstone 5) Foundation 6) Fundament 7) Plantingtheseed 8) Provision 9) Substantiality 10) Support 11) Training 12) Understructure 
• (n.) That which forms the foundation or support of anything; the basis; the essential or fundamental part; first principle.
Ground'work` (-wûrk`) noun That which forms the foundation or support of anything; the basis; the essential or fundamental part; first principle. Dryden. 
Lead rope and lunge-line training. 
noun preliminary preparation as a basis or foundation; `we are prepared today because of groundwork that was done ten years ago`
See Baseboard.