The Proto-Turkic word *kạt-
Word *kạt-
Meaning hard

Comments
S. A. Starostin, A. V. Dybo, O. A. Mudrak - An Etymological Dictionary of Altaic Languages, 2003, Brill

Other words that might be of interest
*dɨŋla- / diŋle- ‘to listen, hear’