American Heritage Dictionary
(1)
Century Dictionary
(3)
GNU Webster's 1913
(1)
WordNet
(1)
Elsewhere on the web
Pi (dreadful), Requiem for a Dream (overreaching, lugubrious, and ultimately flaccid).— The Full Feed from HuffingtonPost.com
Tone: A little lugubrious (just like the movie), because Jaoui insists on avoiding a translator's services and speaks in halting French instead.— GreenCine Daily
But his eyes looked lugubrious, as if he felt he had not deserved so much bad luck, and there were bilious lines beneath them So Mr. May, in his room in the Moon and Stars, which was the best inn in Woodhouse--he must have a good hötel--lugubriously considered his position.— The Lost Girl
Mr. Nash inquired Any heart--or any manners Peter Sherringham made the secret reflexion that he liked her better lugubrious, as the note of pertness was not totally absent from her mode of emitting these few words.— The Tragic Muse

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