Is it under way or underway?

Both of these expressions exist in British English. They do, however, have different meanings.

Under way

This is used to mean that something is happening/going ahead.

Examples:

  • The project is now under way.
  • It was not long before their journey was under way.

Underway

This is an adjective (or describing word), meaning ‘occurring while in motion’.

Example:

  • We are going to try underway refuelling.