Wordnet 3.0
NOUN (1)
1. 
 an act of scaling by the use of ladders (especially the walls of a fortification); 
VERB (1)
1. 
 climb up and over; 
- Example: "They had to escalade canyons to reach their destination"
The Collaborative International Dictionary of English v.0.48:
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.
   [1913 Webster]
         Sin enters, not by escalade, but by cunning or
         treachery.                               --Buckminster.
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
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.
   [1913 Webster]
WordNet (r) 3.0 (2006):
escalade
    n 1: an act of scaling by the use of ladders (especially the
         walls of a fortification)
    v 1: climb up and over; "They had to escalade canyons to reach
         their destination"