noun
merging car; vehicle merging into a lane
Used in traffic contexts for a car that is entering a main road or changing lanes to join the flow of traffic.
高速道路で合流車に注意してください。
Please watch out for merging cars on the expressway.
合流車がスムーズに入れるように車間距離をあけましょう。
Let's leave enough space so that merging vehicles can enter smoothly.