Seventh (adjective)

1. Constituting number seven in a sequence.
2. Occurring in position number seven.

Origin:

From middle english seventhe, seofteþe, from old english seofontēoþa, from proto-germanic *sebuntōdō (“seventh”), from *sebun (“seven”) + *-tōdō (ordinal suffix).

Examples:

1. She was the seventh person in line.
2. The seventh inning stretch is a tradition at baseball games.
3. The seventh month of the year is July.
4. The book in the series is called 'Harry Potter and the Deathly Hallows', the seventh in the series.
5. The seventh son of a seventh son is said to be particularly gifted.