Definition of slap on
: to add (something, such as an extra charge) to an amount The hotel slapped an extra $100 on his bill to cover the damage. The judge slapped on an additional fine.
Word by Word Definitions
: opening, breach
: to strike sharply with or as if with the open hand
: to cause to strike with a motion or sound like that of a blow with the open hand
: to put, place, or throw with careless haste or force
: a quick sharp blow
: a blow with the open hand
: a noise like that of a slap
: directly, smack
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