From The Collaborative International Dictionary of English v.0.48 :
Somnambulation \Som*nam`bu*la"tion\, n. [L. somnus sleep + ambulatio a walking about, from ambulare to walk. See Somnolent, Amble.] The act of walking in sleep, called also sleepwalking. [1913 Webster]From WordNet (r) 3.0 (2006) :
somnambulation n 1: walking by a person who is asleep [syn: sleepwalking, somnambulism, somnambulation, noctambulism, noctambulation]