Lox and Oxygen

Lox noun - A bluish translucent magnetic liquid obtained by compressing gaseous oxygen and then cooling it below its boiling point; used as an oxidizer in rocket propellants.

Oxygen and lox are semantically related. In some cases you can use "Oxygen" instead a noun "Lox".

Oxygen noun - A nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust.

Lox and oxygen are semantically related. Sometimes you can replace term "Lox" with "Oxygen", this nouns are similar.