Here's why:
* It combines two words: "tape" and "recording."
* It functions as a single unit: It refers to a specific type of recording, not just a tape or a recording in general.
* The meaning is different from the individual words: "Tape" by itself means a strip of material, and "recording" by itself means the act of capturing sound or images. "Tape recording" is a specific form of recording that uses tape.
Therefore, "tape recording" meets all the criteria of a compound noun.