apostatize

intr.v., -tized, -tiz·ing, -tiz·es.
To abandon one's religious faith, a political party, one's principles, or a cause.

verb

To abandon one's cause or party usually to join another: defect, desert, renegade, tergiversate, turn. Slang rat. Idioms: change sides, turn one's coat. See approach/retreat, trust/distrust.

Note: click on a word meaning below to see its connections and related words.

The verb has one meaning:

Meaning #1: abandon one's beliefs or allegiances
  Synonyms: apostatise, tergiversate

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