on the way; en route
Used for physical movement or travel; often appears with verbs like 行く, 来る, or in phrases such as ～の途上で.
On the way to the business trip, I read the documents on the Shinkansen.
He had an accident on his way home.
in the process of; in the middle of
Abstract use for ongoing development, construction, or progress; commonly follows nouns like 発展, 建設, 成長.
The country is in the process of development.
The new building is still in the middle of construction.
I got into an accident on the way to the airport.
This country's economic development is still in progress.