noun, masculine/ve.lo a pnø syʁ.di.mɑ̃.sjɔ.ne/plural: vélos à pneus surdimensionnés
vélo à pneus surdimensionnés is masculine in French.
a fatbike; synonym of fat bike (a bike for riding on trails of ice and snow)
Related: VPS
From vélo (“bike”) + pneu (“tyre”) + surdimensionné (“oversized”). From being a bicycle with oversized tires.