• An implement used to consolidate concrete or mortar in molds or forms.
  • A hand-operated device for compacting flooring topping or other unformed concrete by impact from the dropped device in preparation for strikeoff and finishing. Contact surface often consists of a screen or a grid of bars to force coarse aggregates below the surface that prevents interference with floating or trowelling. See also jitterbug.


  • A material which is placed around the core of a nuclear reactor to reflect neutrons back to said core, preventing their escape. Also called reflector (4).
  • To interfere in a harmful or unauthorized manner. For example, to tamper with a delicate mechanism without the proper expertise.

Origin & History of “tamper”

Tamper began life as a variant of temper. It originally meant ‘mix clay together with water to make it suitable for use’. However, the notion of ‘mixing’ seems to lead on naturally to ‘interference’ (meddle originally meant ‘mix’), and by the end of the 16th century we find that ‘tampering with clay’ had moved on to ‘tampering with anything’ – ‘interfering’ with it.