from the GNU version of the Collaborative International Dictionary of English
- transitive v. To renounce.
from The Century Dictionary and Cyclopedia
- To renounce absolutely.
From Medieval Latin abrenunciare, from Latin ab- ("from") + renuntio ("revoke"). (Wiktionary)
Many of these might seem ingrate and unkind children, that will no better acknowledge and recognise their parents in words and outward pretence, but abrenounce and cast them off, as though they hated them as dogs and serpents.