C15 

A code used, usually by guys, when an attractive woman(women) is(are) somewhere nearby and the other guys need to be notified without alerting said attractive woman(women) that she(they) is(are) being observed.

This is usually used in an office atmosphere, in a retail chain outlet over the loudspeaker or in mixed company.

Steve: "John, did you see the C15 in the software aisle?"
John: "Oh yeah...she was definitely a C15!!"
or
John: "We had a C15 at the front desk today around 2:00."
Steve: "Oh, I wasn't aware."
Boss: "Where are my TPS reports? And what is a C15?"
John & Steve: *laughs*

C15 by Cowski June 19, 2010

c15rli

c15rli is a fanpage of charli who is famous for nothing and she is very ignerent

c15rli is so hot

c15rli by hello917371931 January 31, 2021

C151

A train rolling stock on the Singapore Mass Rapid Transit network serving the North–South, and East–West lines, operated by SMRT Trains and manufactured by Kawasaki Heavy Industries (1987–2026).

It's so sad that the C151s are getting scrapped.

C151 by Uzi Doorman February 18, 2024