Parashas Toldos · Passuk 25:30
And Esav said to Yaakov, “Give me some of that red stuff to gulp down, for I am exhausted”—which is why he was called Edom.
Rashi on Bereishis 25:30 (classical source on this passuk; not listed as a numbered Torah Temimah unit here).
Lemma / focus: הלעיטני.
English: I will open my mouth and you pour a great deal into it—as we learned: one does not force-feed a camel, but one may pour food into its mouth.
Derash on the verse (Rashi / mishnaic usage) — not a formal named middah of the 13: the rare verb is fixed by its mishnaic sense of pouring food into an animal’s mouth.
Esav asked to have the red stew poured into his open mouth like an animal; from that red stuff he was called Edom.