Report Abuse. Lobster is slang for a person who is sunburnt, is an expression of contempt for a gullible, awkward, bungling, or undesirable person, and was old British slang for a soldier, on account of the red uniform.eport Abuse. Lobster is slang for a person who is sunburnt, is an expression of contempt for a gullible, awkward, bungling, or undesirable person, and was old British slang for a soldier, on account of the red uniform.