1) Different 2) Foreign 3) Foreign or strange 4) Not acquainted 5) Not conversant about 6) Not familiar 7) Not known or well known 8) Not well known 9) Strange 10) Unaccustomed 11) Unacquainted 12) Unacquainted with 13) Unfamiliar with 14) Unknown 15) Unusual 1) Foreign 2) New 3) Strange 4) Unacquainted 5) Uncharted 6) Unidentified 7) Unknown 
[adj] - not known or well known
adjective not known or well known; `a name unfamiliar to most`; `be alert at night especially in unfamiliar surroundings`
not familiar; not acquainted with or conversant about: to be unfamiliar with a subject. · different; unaccustomed; unusual; strange: an unfamiliar treat.
[TEKS ELAR vocabulary] not known or well known