9-letter words
ending in SION.

A crash between two things.

Not understanding what is happening.

Slowly being worn away, such as metal rusting.

Spreading out, such as a smell through a room.

A measurement such as length, width or height.

A different route when a road is closed; something fun to do.

Leaving someone or something out.

A short trip, often with a group.

Getting bigger.

A sudden loud burst, like a bomb going off.

Being forced to leave a place, such as a school.

An extra part added to a building; extra time.

Being completely covered by a liquid.

Collapsing inwards suddenly.

Making sure everyone is part of something.

Going somewhere you are not wanted.

Turning something upside down or back to front.

Being very exact and accurate.

Supplying something; food and supplies for a journey.

Pushing away, like two magnets that will not touch.

A strong feeling of disgust.

Being private and away from other people.