sneak up (on someone or something)(redirected from sneaking up on)
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sneak up (on someone or something)
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.
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.
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!