The Collaborative International Dictionary of English v.0.48:

Sens \Sens\, adv. [See Since.]
   Since. [Obs.] --Spenser.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sens
    n 1: street names for marijuana [syn: pot, grass, green
         goddess, dope, weed, gage, sess, sens, smoke,
         skunk, locoweed, Mary Jane]