I don't know for certain, but I suspect Adobe introduced its 'loupe tool' in 1987 when it released Photoshop. Whether or not 'loupe' is pretentious, it is now a ubiquitous term in the software industry. It's also four syllables shorter than 'magnifying glass' which, in my view (and when correctly spelled!), absolves it.
You mean the magnifying glass during text selection?