/ Dictionary / Index L lassie: Meaning and Definition of Find definitions for: las•sie Pronunciation: (las'ē), [key] — n. a young girl; lass. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: lassie (Thesaurus) Lassen Volcanic National Park lassitude Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language