Parashas Kedoshim · Passuk 19:03
Chabad.org — English translation + Rashi
Torah Temimah · Toras Kohanim / Yoreh Deah tradition.
English: What is mora? He does not stand in his [parent’s] place, nor sit in his place, nor contradict his words, nor tip the scales against him.
Halachic definition of mora
Mora is expressed in concrete restraint: not occupying the parent’s seat, not openly contradicting, and not declaring another’s opinion superior in the parent’s presence.