I had a feeling I'd be enlightened on this point. Like this is the first time it's ever been discussed.......
But I'm sticking by my guns!!! (If nothing else, the understanding I favor is more specific, whereas making "pistol" synonymous with "handgun" makes the term less specific). I shant push my preferences on others, however.
as usual, Wikipedia gives an interesting treatment:
Some handgun subtypes include single-shot pistols, revolvers, semi-automatic pistols, and fully automatic, or machine pistols.
The overlapping variations in meaning of the words "pistol" and "handgun" are discussed below.
[edit] Multiple senses of the word "pistol"
The word "pistol" is often synonymous with the word "handgun". Some handgun experts make a technical distinction that views pistols as a subset of handguns.[citation needed] In American usage, the term "pistol" refers to a handgun whose chamber is integral with the barrel, making pistols distinct from the other main type of handgun, the revolver, which has a revolving cylinder containing multiple chambers. However, Commonwealth usage makes no distinction at a technical level—"pistol" may refer to revolvers, semi-automatics, or muzzle-loading/cap-&-ball handguns. For example, the official designation of the Webley Mk VI was "Pistol, Revolver, Webley No. 1 Mk VI", and the designation "Pistol No. 2 Mk I" was used to refer to both the Enfield Revolver and the later Browning Hi-Power semi-automatic.[1],[2],[3],[4]
In the 15th century the word "pistol" was used for small knives and daggers which could be concealed in a person's clothing.[citation needed] By the 18th century, the term came to be used exclusively to refer to handheld firearms. Practical revolver designs appeared in the 19th century, and it was in that century that the (sometimes-observed) technical differentiation in usage of the words "pistol" and "revolver" developed.[citation needed]