Longman Dictionary of Contemporary English - slap

~1 v slapped, slapping 1 to hit someone quickly with the flat part of your hand  (Do you think it's OK to slap children if they're really rude? | slap sb on the back (=hit them on the back in a friendly way)) 2 T always + adv/prep to put something down noisily on a surface, especially when you are angry  (slap sth on/down)  (I slapped the report down on his desk and told him to do it again.) 3 to hit a surface, making a sound like someone being slapped noisily + agains  (Small waves slapped against the jetty) slap sb down phr v to unfairly and unkindly criticize someone so that they lose confidence slap sth on phr v informal 1 to put or spread something quickly or carelessly onto a surface  (She rushed upstairs and slapped on some make-up.) 2 to suddenly announce a new charge, tax etc, especially unfairly or without warning  (Many tour operators slap on supplements for single people.) ~2 n 1 a quick hit with the flat part of your hand  (give sb a slap)  (Julia gave Roy a friendly slap on the cheek.) 2 a slap in the face an action that seems to be deliberately intended to offend or upset someone, especially someone who has tried very hard to do something  (When I wasn't promoted it felt like such a terrible slap in the face.) 3 a slap on the wrist informal a punishment that is not very severe ~3 also slap-bang ~ adv informal hitting something very hard, especially when you are running, driving etc + into  (I ran slap-bang into a lamp-post.)