Source : Webster's Revised Unabridged Dictionary (1913)

Tangency \Tan"gen*cy\, n.
   The quality or state of being tangent; a contact or touching.

Source : WordNet®

tangency
     n 1: the state of being tangent; having contact at a single point
          or along a line without crossing
     2: (electronics) a junction where things (as two electrical
        conductors) touch or are in physical contact; "they forget
        to solder the contacts" [syn: {contact}]