Lewis & Short

suspĭcax, ācis, adj. [suspicor], apt to suspect, distrustful, suspicious.

  1. I. Lit. (very rare): populus suspicax ob eamque rem mobilis, Nep. Timoth. 3, 5: frater, Liv. 40, 14: animus alicujus, Tac. A. 1, 13.
  2. II. Transf., that excites mistrust, suspicious: silentium, Tac. A. 3, 11 fin.; Sen. Ira, 2, 29, 2 (dub.; bracketed by Haase).