Source : Webster's Revised Unabridged Dictionary (1913)

Escalade \Es`ca*lade"\, n. [F., Sp. escalada (cf. It. scalata),
   fr. Sp. escalar to scale, LL. scalare, fr. L. scala ladder.
   See {Scale}, v. t.] (Mil.)
   A furious attack made by troops on a fortified place, in
   which ladders are used to pass a ditch or mount a rampart.

         Sin enters, not by escalade, but by cunning or
         treachery.                               --Buckminster.

Escalade \Es`ca*lade"\, v. t. [imp. & p. p. {Escaladed}; p. pr.
   & vb. n. {Escalading}.] (Mil.)
   To mount and pass or enter by means of ladders; to scale; as,
   to escalate a wall.

Source : WordNet®

escalade
     n : an act of scaling by the use of ladders (especially the
         walls of a fortification)

escalade
     v : climb up and over; "They had to escalade canyons to reach
         their destination"