sev·en·teen 
(sĕv′ən-tēn)
(sĕv′ən-tēn)n.
1. The cardinal number equal to 16 + 1.
2. The 17th in a set or sequence.
[Middle English seventene, from Old English seofontīne; see sept in the Appendix of Indo-European roots.]
sev′en·teen adj. & pron.