somnambulist

noun

Etymology: Borrowed from French somnambuliste, from Medieval Latin somnambulus (“sleepwalker”). By surface analysis, somn- + -ambulist.

1. A person who walks about in their sleep; a sleepwalker.

   “The clergyman floundered a moment, as is usual with an absent man who is recovering the train of his ideas, or a somnambulist when he is suddenly awakened.”

   “The slim one got up and walked straight at me - still knitting with downcast eyes - and only just as I began to think of getting out of her way, as you would for a somnambulist, stood still, and looked up.”