Lox is salmon prepared so it keeps, then eaten cold in very thin slices. In Jewish-American food, especially in New York, it is the salty salmon that goes on a bagel with cream cheese. Classic lox is salmon cured in salt, not cooked and not always smoked; many shops and speakers also call smoked salmon lox, so people stretch the word past the tidy “smoked” line. It is a food word, at home on a menu, not in a formal essay. The name comes from Yiddish laks, “salmon.” Scientists also write LOX for liquid oxygen — same letters, different word, nothing to eat.