This is the 286th most frequent Finnish word.
viiden
"Viiden" means "of five" or "five's" in English.
Here, 'viiden' is used in the genitive case of the number five to indicate a time reference.
Saavun asemalle viiden jälkeen.
I will arrive at the station after five.
In this sentence, 'viiden' describes the characteristic of 'tähtiä' (stars), used in a compound as an attributive modifier.
Tämä on viiden tähden hotelli.
This is a five-star hotel.
Here, 'viiden' is again in the genitive case, modifying 'metriä', specifying the measurement of the length.