Lewis & Short

tensĭo, ōnis, f. [tendo], a stretching, stretching out, extension (post-Aug. and very rare).

  1. I. In gen.: papilionum, a setting up, pitching, Hyg. Gromat. init.
    Plur.:     bracchia, quae in eas tensiones includuntur, Vitr 1, 1 med.
  2. II. In partic., a tension or contraction of the nerves, as a disease: nervorum, Scrib. Comp. 101; 255: praecordiorum, id. ib. 260; Veg. Vet. 1, 53 fin.