- An envelope of neutron-reflecting material in a nuclear weapon, used to delay the expansion of the reacting material and thus produce a longer-lasting and more energetic explosion.
- A tool used to tamp something down, such as tobacco in a pipe.
- A person or thing that tamps.
- (in professional sports) To discuss future contracts against league rules with a player.
- (intransitive) To alter by making unauthorized changes; to meddle.