unaccustomed

unaccustomed /ˌʌnəˈkʌstəmd/ adjective
unaccustomed
/ˌʌnəˈkʌstəmd/
adjective
Britannica Dictionary definition of UNACCUSTOMED
formal
1 
: not usual or common : not customary
2 
: not familiar with something so that it does not seem normal or usual : not used to something — + to