vain

Not yielding the desired outcome; fruitless.

Lacking substance or worth.

Having or showing excessive pride in one’s appearance or accomplishments; conceited.

Foolish.

(in vain) To no avail; without success.

(in vain) In an irreverent or disrespectful manner.

Having no real value or importance; worthless; unsubstantial; empty; trivial; idle.

Producing no good result; destitute of force or efficacy; fruitless; ineffectual; useless; futile; unavailing.

Light-minded; foolish; silly.

Proud of petty things or of trifling attainments or accomplishments; elated with a high opinion of one’s personal appearance, manners, or the like; courting the admiration or applause of others; conceited; self-complacent; also, proceeding from or marked by such pride or conceit: as, to be vain of one’s figure or one’s dress.