1. A route or course traveled alone, often with a sense of isolation or solitude
She walked down the lonely path through the forest.
Ela caminhou pelo caminho solitário através da floresta.
2. Figuratively, a difficult journey or life experience undertaken without support or companionship
He chose a lonely path in his career, refusing to compromise his principles.
Ele escolheu um caminho solitário em sua carreira, recusando-se a comprometer seus princípios.