useless

adjective4

1. •
   not helpful in any way, or bringing no good result

   • I think it's useless to keep this discussion going. It's like talking to a brick wall.
   • I tried my best to make him quit smoking, but my efforts were useless. He now smokes six packs a day.
2. •
   Without use or the possibility to be used.

   • This fork's prongs are bent. It's useless now.
3. •
   Good-for-nothing; not dependable.

   • Bill never mows the lawn, takes out the trash or anything. He's useless, but I love him anyways.
4. •
   (informal) Of a person, Unable to do well at a particular task or endeavor.

   • My brother is useless at most computer games, but he is an awesome PS2 player.
   • Why do you keep trying? You're obviously useless at it.