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double-O

American  
[duhb-uhl-oh] / ˌdʌb əlˈoʊ /

noun

Older Slang.

plural

double-Os
  1. careful scrutiny or close inspection.


Etymology

Origin of double-O

1915–20; after the two o 's in once-over

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"Let's just say it's got a double-O in the title."

From BBC

“All right, hey, everybody. Weird, weird day. But I’ve got a Cooter Brown brown ale and a Martin double-O-21 from 1963 and I’m in my little writin’ shed.

From Washington Times

It’s 1950, and the spy has just been promoted to Double-O status, replacing a murdered agent.

From Seattle Times

The double-O represents bike wheels.

From The Guardian

Sherlock's no brain-box but become double-O.

From BBC