Or search: physics, resolve, refract, astigmia, meniscus, aberrate, aspheric, aplanatic, collimate, stigmatism, aspherical, catoptrics, holography, astigmatism, apochromatic
2 Syllables: SU
audit, clotted, cockpit, dotted, jotted, knotted, lauded, nodded, opted, optic, plaudits, plotted, potted, prodded, Roderick, rotted, spotted, squatted, topic, toxic, tropic, trotted
3 Syllables: USU
allotted, applauded, aquatic, chaotic, defrauded, despotic, erotic, exotic, hypnotic, narcotic, neurotic, quixotic, spasmodic, synopsis, unspotted
4 Syllables: UUSU
episodic, idiotic, microscopic, patriotic, periodic, philanthropic, superadded
5 Syllables: UUUSU
antibiotics

Found 45 words across 4 groupings. Skipped 3 excess words of a similar stem.