10x · adjective1
A homoglyphic form of 10× that is easy to type on a keyboard without going out of one's way for the non-keyboard character. In trivial homoglyphic use as math notation for many decades but not particularly common adjectivally as /ˈtɛnˌɛks/ until the 21st century.
10x · interjection2
From the similarity in pronunciation of ten + /ks/ to thanks.
Etymology from Wiktionary, CC BY-SA 4.0.