1.  reactor(n = noun.artifact) - an electrical device used to introduce reactance into a circuit;
is a kind of electrical device
has particulars: coil

2.  reactor(n = noun.artifact) nuclear reactor - (physics) any of several kinds of apparatus that maintain and control a nuclear reaction for the production of energy or artificial elements;
is a kind of apparatus, setup
has parts: control rod, core, moderator
has particulars: atomic pile, atomic reactor, chain reactor, pile, breeder reactor, fast reactor, gas-cooled reactor, liquid metal reactor, thermal reactor, fusion reactor, thermonuclear reactor, water-cooled reactor

1.  A choking coil. [Webster 1913 Suppl.]

2.  A nuclear reactor. [PJC]

reactor, n.
1 a person or thing that reacts.
2 (in full nuclear reactor) an apparatus or structure in which a controlled nuclear chain reaction releases energy.
3 Electr. a component used to provide reactance, esp. an inductor.
4 an apparatus for the chemical reaction of substances.
5 Med. a person who has a reaction to a drug etc.

atomic reactor, boiling water reactor, breeder reactor, chain reactor, chemical reactor, fast reactor, fusion reactor, gas-cooled reactor, liquid metal reactor, nuclear reactor, power reactor, pressurized water reactor, thermal reactor, thermonuclear reactor, water-cooled reactor