do a mischief



do yourself a mischief

  (British & Australian humorous)
if you tell someone they will do themselves a mischief if they do something, you mean they will hurt themselves You want to be careful jumping over spikes like that - you might do yourself a mischief!
See also: mischief

Common Names:

NameGenderPronouncedUsage
Yaromil-Medieval Slavic (Hypothetical)
ÉLiÁS-Hungarian
Coy[kɔi]
Justina[dʒəs'ti:nə]
Kristjan-Estonian, Slovene
Magdalina-Old Church Slavic, Bulgarian