/ Dictionary / Index G Geissler tube: Meaning and Definition of Find definitions for: Geiss'ler tube" Pronunciation: (gīs'lur), [key] a sealed glass tube with platinum connections at the ends, containing rarefied gas made luminous by an electrical discharge. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. geisha geitonogamy Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language