Question: what is the definition of the root ex?
Answer: 1. SEE SYNONYMS FOR ex- ON THESAURUS.COM. a prefix meaning “out of,” “from,” and hence “utterly,” “thoroughly,” and sometimes meaning “not” or “without” or indicating a former title, status, etc.; freely used as an English formative: exstipulate; exterritorial; ex-president (former president); ex-member; ex-wife.