lock on

lock on (to) (someone or something)

1. To become able to automatically track and target someone or something. We've locked on the enemy ship, sir. Permission to fire? The fighter jet had locked on to us, so there was no option except to eject.
2. To fix one's gaze onto someone or something; to stare at someone or something with intensity. He locked on to a wealthy businessman on the other side of the bar who looked like the perfect target for his scam.
3. To fasten, attach, or grab onto someone or something, especially with great speed or intensity. He locked on to the suitcase and refused to let go. My son locked on to my leg when the man came up to talk to us.
See also: lock, on
Farlex Dictionary of Idioms.

lock on (to someone or something)

to fasten or grab onto someone or something. She locked onto the child and wouldn't leave his side for an instant. I saw the thing 1wanted and locked on.
See also: lock, on
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

lock on

v.
1. To aim something at a moving target so as to follow it automatically: The pilot locked the heat-seeking missile on its target.
2. To stare at someone or something intently; fix one's gaze on someone or something: The detective's eyes locked on the suspicious package under the desk.
See also: lock, on
The American Heritage® Dictionary of Phrasal Verbs.
See also:
  • lock on (to) (someone or something)
  • go around
  • go around doing
  • gain ground on (someone or something)
  • locked down
  • hurl (someone or something) into (something)
  • hurl into
  • firing line
  • automatic
  • pilot