ex·ci·ton 
(ĕksĭ-tŏn′, -sī-)
(ĕksĭ-tŏn′, -sī-)n.
An electrically neutral excited state of an insulator or semiconductor, often regarded as a bound state of an electron and a hole.
[EXCIT(ATION) + -ON1.]
- irreducibly
- irrefragability
- irrefragable
- irrefragably
- irrefrangible
- irrefrangibly
- irrefutability
- irrefutable
- irrefutably
- irreg.
- irregardless
- irregular
- irregular galaxy
- irregularity
- irregularly
- irrelative
- irrelatively
- irrelevance
- irrelevancy
- irrelevant
- irrelevantly
- irreligion
- irreligious
- irreligiously
- irreligiousness