From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): ( a.) One more than sixteen; ten and seven added; as, seventeen years.

(2): ( n.) A symbol denoting seventeen units, as 17, or xvii.

(3): ( n.) The number greater by one than sixteen; the sum of ten and seven; seventeen units or objects.

King James Dictionary [2]

Sev'Enteen, a. seven-ten. Seven and ten.