Polytropic rhymes with:
telescopic, capek, chapek, daubenspeck, doverspike, endoscopic, epic, filipek, geotropic, gyroscopic, isotopic, knapik, kopec, kupek, laparoscopic, leppek, microscopic, monocarpic, myopic, nitpick, olympic, opic, paralympic, perpich, phenotypic, philanthropic, philippic, polycarpic, popek, popick, popik, salopek, scopic, sepik, slupic, telescopic, topic, tropic