adverb
straight; directly; without detour
Adverbial use meaning going straight toward a destination or goal, often with a sense of single-mindedness.
彼は空港へ一路向かった。
He headed straight for the airport.
成功を目指して一路邁進する。
I push forward single-mindedly aiming for success.
noun
straight road; direct route; journey; voyage
Noun use; can refer to a literal straight road, a direct route, or a metaphorical journey. The 'voyage' sense is somewhat literary.
この一路をまっすぐ行けば駅に着く。
If you go straight along this road, you'll reach the station.
人生は長い一路だ。
Life is a long journey.
Compound of 一 (one) and 路 (road, path). The adverbial use developed from the idea of a single, undeviating road.