To superimpose is to put something over something else.(verb)
An example of superimpose is when you put a watermark or copyright mark over the top of a picture but the picture underneath is still visible.
See superimpose in Webster's New World College Dictionary
See superimpose in American Heritage Dictionary 4
transitive verb su·per·im·posed, su·per·im·pos·ing, su·per·im·pos·es
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