The driver had to deviate from the planned route due to road construction ahead.

deviate 是动词，由前缀 de-（表示“离开”）和词根 via（“道路”）加上动词后缀 -ate 组成，字面意思是“离开道路”，引申为“偏离、背离”。在句中指“偏离原定路线”。