What is a synonym for was?

There isn't one single perfect synonym for "was" because its meaning can vary depending on the context. Here are some options, depending on the specific nuance you want to convey:

Past Tense:

* Were (plural)

* Used to be

* Existed

* Occurred

* Happened

* Took place

Past Participle:

* Been

* Had

Formal/Literary:

* Did exist

* Had existed

* Once was

Informal:

* Used to

* Once upon a time

For specific situations:

* Died (if referring to death)

* Left (if referring to departure)

* Finished (if referring to completion)

To choose the best synonym, consider the sentence you're writing and what nuance you want to emphasize.