1, The full form of Nos is Numbers. It’s used on Miscellaneous ,Chat slang in Worldwide

Nos. or nos. is an abbreviation of the word “Numbers”

Numbers is a spreadsheet application developed by Apple Inc. as part of the iWork productivity suite alongside Keynote and Pages. Numbers is available for iOS, and macOS High Sierra or newer. Numbers 1.0 on OS X was announced on 7 August 2007, making it the newest application in the iWork suite. The iPad version was released on 27 January 2010. The app was later updated to support iPhone and iPod Touch.

Numbers uses a free-form “canvas” approach that demotes tables to one of many different media types placed on a page. Other media, like charts, graphics and text, are treated as peers. In comparison, traditional spreadsheets like Microsoft Excel use the table as the primary container, with other media placed within the table. Numbers also includes features from the seminal Lotus Improv, notably the use of formulas based on ranges rather than cells. However, it implements these using traditional spreadsheet concepts, as opposed to Improv’s use of multidimensional databases.