Why do we abbreviate the word Number: “No.” when there is no O in Number?
There is a VERY logical answer. (Pet peave: people “explaining” such things by saying “English is weird that way”, when the fact is they simply don’t happen to KNOW the reason for something.) I see that most are relying on the wikipedia answer and copies of it to other sites. The article DOES note that the “o” was originally a “superscript”, or letter raised above the line (and often underlined), as you might still see in a painted sign, it does not explain why THAT specific letter is used, which is, I believe, your question! As many have suggested, “no.” is not based on the English word “number.” It means ‘number’, but like many of our abbreviations (such as etc., i.e., e.g., viz.) it is based on a LATIN word, the word “numero”. But note that the basic form of the word in Latin is “numerus”. “Numero” is the “ablative case” form. Case endings indicate the particular use/function of a noun form in a sentence (something English now does mostly through prepositional phrases and word ORDER
