unsub

noun

un·​sub ˈən-ˌsəb How to pronounce unsub (audio)
plural unsubs
US law enforcement, informal
: the unknown perpetrator of a crime
Not one but two murderous unsubs are on the loose in tonight's Criminal Minds …— TV Guide
Rhyme remembered the thousands of times he'd run crime scenes. Sometimes a miracle would happen. He'd be looking around and somehow ideas about the unsub would come to him. He couldn't explain how.— Jeffery Deaver

Examples of unsub in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The trauma of her shooting and the pressure of her job leads to the BAU agent shooting an unsub. — Alamin Yohannes, EW.com, 10 June 2024 The 40-second clip depicted the BAU agents in a number of different scenarios and suggested Prentiss died after the events with the unsub Ian Doyle in season 6. — Adrianna Freedman, Good Housekeeping, 1 Apr. 2023

Word History

Etymology

unknown (or unidentified) subject

First Known Use

1965, in the meaning defined above

Time Traveler
The first known use of unsub was in 1965

Rhymes for unsub

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Browse Nearby Words

unstylish
unsub
unsubdued
See all Nearby Words

Cite this Entry

“Unsub.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsub. Accessed 27 Mar. 2025.

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