Person who regards his online life as more important than the safety of other pedestrians or traffic. Thinks that the world will fall down unless he can see how many idiots "liked" his idiocy. Akin to the real word "Somnambulist" - "Sleepwalker".
Did you see that phonambulist tripping over the kerb/who ran into the pole.

Donald Chump is not a true phonambulist, he's got a chauffeur.
by Joe Soap1 February 8, 2019
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