Or search: pot, bury, nest, sink, embed, graft, imbed, infix, insert, conjoin, implant, ingraft
2 Syllables: SU
acid, affix, avid, Bassett, blasted, Catholic, classic, drafted, drastic, fasted, gastric, grafted, graphic, Hazlitt, lasted, magic, placid, plastic, tacit, traffic, tragic
3 Syllables: USU
bombastic, dynastic, elastic, fantastic, geographic, gymnastic, monastic, sarcastic, scholastic, thoracic
4 Syllables: UUSU
demographic, ethnographic, inelastic, photographic, telegraphic, topographic
5 Syllables: UUUSU
ecclesiastic, enthusiastic

Found 39 words across 4 groupings. Skipped 6 excess words of a similar stem.