Where does “mozeć” come from?

mozeć (Polish) comes from Polish -ć, from Proto-Slavic -ťi, from Proto-Slavic -kti.

Ancestry of “mozeć”, step by step

StepLanguageWordMeaning
1Polish-ćforms generic infinitives of stems ending in vowels
2Proto-Slavic-ťiForm of *-ti, used with root-stem verbs ending in...
3Proto-Slavic-kti—
Every word from Proto-Slavic -kti →Every word from Polish -ć →Every word from Proto-Slavic -ťi →