emongifier
(E-Monj-ifier) A pointlessly employed human being, usually in a high vis jacket or with a name tag of some description, doing the job of an inanimate, but perfectly functional sign or instruction, whilst standing next to or in front of that very sign or instruction, as if we can neither see nor understand it.

Usually found at ports, or other areas of high human traffic, next to signs that everyone understands and can clearly see, using their hands or vocals to emphasise what the sign says or means.
It's a good job that emongifier told me to go left, the meaning of the 8 foot long, fluorescent arrow pointing left behind him was a total mystery to me, until he looked at me through half closed eyes and said 'left please mate'. The guy behind me would probably have died if the guy hadn't sufficiently directed him. Long live the Emongifier.