As nouns the difference between rubber and mugger
is that rubber
is (uncountable) pliable material derived from the sap of the rubber tree; a hydrocarbon polymer of isoprene or rubber
can be (sports) a series of an odd number of games or matches of which a majority must be won (thus precluding a tie), especially a match consisting of the best of a series of three games in bridge or whist while mugger
is a street robber or mugger
can be a large crocodile crocodilus palustris
of southwest asia, having a very broad wrinkled snout.
As a verb rubber
is to eavesdrop on a telephone call.