The Collaborative International Dictionary of English v.0.48:

standoffish \stand*off"ish\, stand-offish \stand-off"ish\a.
   Shy or distant in manner; cold; aloof; reserved; not
   friendly.

   Syn: offish.
        [PJC] -- stand*off"ish*ness, n. -- stand*off"ish*ly,
        adv.
        [PJC]