the throat as the passage food goes down: the gullet, the part of you that swallows
This word turns up exactly once in the Hebrew Bible, in a proverb about eating at a powerful man's table: notice what is set before you, and put a knife to your throat if you are a person of large appetite (Proverbs 23:2). It names the throat from the eating side, the tube food and drink go down, and it belongs to a small word family built on the idea of gulping. The verb of that family (לוּעַ) shows up in Obadiah 16, where the nations drink and swallow down the cup of judgment.
Hebrew has a more common word for the throat (גָּרוֹן), and it leans the other way: it is where shouting and singing and praise come from, and it also names the outside of the neck that a chain is hung on. This rare word does not do any of that. It is the swallowing throat, which is why one verse about greed is the only place it was ever needed. Later Hebrew kept it, and it is still an ordinary word for a throat or a gaping opening.
The proverb is playing for a laugh, not making a threat. The knife on the table is the one you eat with, and the joke is that a guest who cannot control himself should point it at his own gullet before he points it at the food. The second half of the verse says why: this is advice for the person who is, in Hebrew, an owner of appetite, using the word usually rendered "soul" (נֶפֶשׁ), which in a context like this one means raw hunger.