1. To pass or move through (something) quickly, surreptitiously, or inconspicuously. I managed to slip through the security check while the guard wasn't looking. We try to block out offensive and disturbing images, but the odd one still slips through our filter. The striker slipped through the other team's defenses and scored a goal.
2. To pass, move, or push something through something quickly, surreptitiously, or inconspicuously. In this usage, a noun or pronoun can be used between "slip" and "through." I slipped the letter through the crack in her door and left before she saw me. The comedian is constantly trying to slip through dirty words without being detected by the network's censors.
slip something through(something)
1. Lit. to cause something to slide or glide through something. The nickel I dropped slipped through the crack in the floor. It rolled toward a crack in the floor and slipped through.
2. Fig. to get something approved without much fuss by a group of people, perhaps by deception. I will try to slip this through the committee. lean slip it through for you.
slip through something
to slide or slither through something narrow or crowded. Gerald slipped through the narrow opening and got away. The dog slipped through the door and ran out into the street.
1. To pass through something gradually, easily, or without being noticed: We slipped through the crowd into the club.
2. To pass something through something gradually, easily, or without being noticed: The tenant slipped the key through the mail slot. He crept up to the barred window of the jail cell and slipped through the keys.