Where does “ចិត្ត” come from?
ចិត្ត (Old Khmer) comes from Sanskrit चित्त, from Sanskrit चित्ति, from Proto-Indo-Iranian *čítˢtiš, from Proto-Indo-European *kʷéyt-ti-s ~ *kʷit-téy-s, from Proto-Indo-European kʷeyt- — to notice; to read.
Ancestry of “ចិត្ត”, step by step