noun
inattention to the road ahead; not watching where one is driving
Used especially in traffic contexts for failing to pay attention to what is ahead while driving or cycling.
事故の原因は前方不注意だった。
The cause of the accident was inattention to the road ahead.
前方不注意で前の車に追突した。
I rear-ended the car in front because I wasn't watching the road.
脇見運転 refers specifically to looking away from the road (e.g., at a phone or scenery), while 前方不注意 is broader and includes simply not paying attention to what is ahead.
Compound of 前方 (front, ahead) and 不注意 (carelessness, inattention).