English: tachograph
Welsh: tacograff
Subject: Trafnidiaeth
English definition: An instrument fitted to commercial vehicles to record mileage, speed, number and location of stops etc.
Welsh context: Termau o’r Memorandwm Esboniadol ar gyfer y Mesur Arfaethedig ynghylch Diogelwch ar Gludiant i Ddysgwyr (Cymru).