malcontent
To cause discontent or dissatisfaction.
obsolete, transitive
[…] James Bond adventure with a Ward Bond delivery, reams of malcontenting and anti-literary remarks, first-class manipulation of Anglo-Saxon's juicier words, and quotations from the Great Books and from William Kite's notebook.
Where it comes from
From Middle French malcontent, from mal- + content; compare Late Latin malecontentus.
Adapted from the Wiktionary entry malcontent (CC BY-SA 4.0).