JQL query when picking from a custom list

[Ops User 2]

I've created a custom list, and I want trigger an event on zapier when the word from that customfield is chosen

[Nic Brough -Adaptavist-]

Do you mean when the user selects a value on-screen, or when they create/edit an issue that has a certain selection made?

[Ops User 2]

When the issue is being edited, after the creation of the ticket

[Nic Brough -Adaptavist-]

Ok, but do you mean when they are actively in the screen and entering the field, or when they submit their changes?

[Ops User 2]

When the issue has been edited and changed

[Nic Brough -Adaptavist-]

Ok, you'll need to create an automation or listener that can say "when field changes, check new value and poke Zapier with it".