1. unsub - Noun
2. unsub - Verb
unsub (plural unsubs)
(law enforcement) Abbreviation of unknown subject. of an investigation.
unsub (third-person singular simple present unsubs, present participle unsubbing, simple past and past participle unsubbed)
Abbreviation of unsubscribe.
Abbreviation of unsubscription.
Abbreviation of unsubscriber.
Source: en.wiktionary.org