/ Thesaurus / H Synonyms of heaviside layer Find synonyms for: Noun1. Heaviside layer, Kennelly-Heaviside layer, E layer, E regionusage: a region of the ionosphere (from 50 to 90 miles up) that reflects radio waves of medium lengthWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language