/ Dictionary / Index C clamshell door: Meaning and Definition of Find definitions for: clam'shell door" Pronunciation: [key] Often,a door consisting of two panels that spread open vertically, as those located on the underside of some cargo planes. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. clamshell clamworm Related Content Daily Word Quiz: reclusive Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language