absorber

n. person or thing which absorbs; person or thing which takes in

In high energy physics experiments, an absorber is a block of material used to absorb some of the energy of an incident particle. Absorbers can be made of a variety of materials, depending on the purpose; lead and liquid hydrogen are common choices.Most absorbers are used as part of a detector. A more recent use for absorbers is for ionization cooling, as in the International Muon Ionization Cooling Experiment.
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Noun
1. (physics) material in a nuclear reactor that absorbs radiation
(hypernym) absorbent material, absorbent
(derivation) absorb, suck, imbibe, soak up, sop up, suck up, draw, take in, take up
(classification) physics, physical science, natural philosophy

n. absorber, person or thing which sucks in; person or thing which takes in

v. absorb; drink; occupy; assimilate; dope, imbibe; siphon