Not having glacial drift deposits; describing areas that were not covered by glaciers during the ice age, or more generally, lacking drift or aimlessness.
From 'drift' plus the suffix '-less' (without). In geology, it specifically means areas untouched by glaciation and therefore lacking glacial drift materials.
The Driftless Area of the Upper Midwest became famous because glaciers mysteriously skipped over it during ice ages—scientists still debate why this Wisconsin-Minnesota-Illinois region escaped when everything around it was buried.
Complete word intelligence in one call. Free tier — 50 lookups/day.