| adj.  vain·er, vain·est Idiom: 1.  Not yielding the desired outcome; fruitless: a vain attempt. 2.  Lacking substance or worth: vain talk. 3.  Having or showing excessive pride in one's appearance or accomplishments; conceited. 4.  Archaic   Foolish.  in vain 1.  To no avail; without success: Our labor was in vain. 2.  In an irreverent or disrespectful manner: took the Lord's name in vain. [Middle English, from Old French, from Latin vānus, empty; see  euə- in the Appendix of Indo-European roots.] vainly adv. vainness n. Synonyms:  vain, empty, hollow, idle, otiose These adjectives mean lacking value or substance: vain regrets; empty pleasures; hollow threats; idle dreams; otiose theoretical discussions. See Also Synonyms at futile. | 
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