prepense
Concise Oxford English Dictionary © 2008 Oxford University Press:
prepense /prɪˈpɛns/
▶adjective [usu. postpos.] chiefly Law, dated deliberate; intentional.
– derivatives
prepensely adverb.
prepensely adverb.
– origin C18: alt. of prepensed, past part. of obs. prepense, from OFr. purpenser, from por- ‘beforehand’ + penser ‘think’.
'prepense' also found in these Oxford entries:

