sneak up (on someone or something)

sneak up (on someone or something)

1. To approach someone or something in a sneaky, furtive manner so as not to be noticed. Don't sneak up on me like that—you frightened the life out of me! We don't want the guards to see us, so we'll need to sneak up from the back.
2. To come up on someone or some group gradually or without being noticed. I've been so busy with my work that our wedding anniversary completely snuck up on me. The deadline is sneaking up on us, and we still haven't made any substantial progress.
See also: sneak, someone, up
Farlex Dictionary of Idioms.

sneak up on someone or something

to approach someone or something quietly and in secret. Please don't sneak up on me like that. I sneaked up on the cake, hoping no one would see me. someone did.
See also: on, sneak, up
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

sneak up

v.
1. To move or operate furtively or surreptitiously toward someone: The thief sneaked up behind the tourists and stole their luggage.
2. sneak up on To approach suddenly and surprisingly: The first day of spring sneaked up on me and I still hadn't gone skiing yet. Don't sneak up on me like that!
See also: sneak, up
The American Heritage® Dictionary of Phrasal Verbs.
See also:
  • sneak up
  • sneak up on
  • slip up on
  • slip up on (someone or something)
  • steal up on
  • steal up on (someone or something)
  • sneak out
  • sneak out (of some place)
  • spied
  • spy on (someone or something)