fifth (Adjective) — Coming next after the fourth and just before the sixth in position.
fifth (Noun) — A quantity of liquor equal to one fifth of a United States gallon.
fifth (Noun) — Position five in a countable series of things. ex. "he was fifth out of several hundred runners"
fifth (Noun) — One part in five equal parts.
fifth (Noun) — The musical interval between one note and another five notes away from it.