10Xer UK /ˌtɛnˈɛks.ə/US /ˌtɛnˈɛks.ɚ/ noun1 •A particularly talented and productive engineer, thought to be capable of doing the work of ten typical engineers.Richard's a 10Xer, I'm, like, barely an Xer. I kinda suck. — 2014 forms10Xers