To strike the palms of( one' s hands together: [ no object] They clapped as the president entered the room. object] We clapped our hands until they ached. to Transgender breast lactation an object against something quickly and wief, producing a sharp sound: object] She clapped the book shut. to put or place quickly or forcefully: on object He clapped on his hat and dashed outside. object on] He clapped handcuffs on the gunman and brought him outside.