Vehement
/ˈviːəmənt/ adjective easyShowing intense feeling or force, especially in expressing a strong opinion.
Her vehement objection to the plan stopped the meeting in its tracks.
Memory Trick
Picture the 'veh-' as a vehicle roaring at full force, since both words trace to a Latin root meaning to carry -- a vehement argument comes at you with that same unstoppable energy.