term:

Abjure

abjure vt

ab·jured
ab·jur·ing
[Latin abjurare, from ab– off + jurare to swear]
: renounce
;specif
: to disclaim formally or renounce upon oath [solemnly s his allegiance to his former country]
ab·ju·ra·tion [ab-jə-rā-shən]
n