MS Project - Can a task deadline have a dependency?

I'm trying to set up a Task Z that has a deadline that is NOT a calendar date, but rather could be expressed as "no later than 180 days after Task X completes." Basically, Task X has variable duration, so its end date is not fixed on the calendar -- and thus, the deadline for Task Z is not a fixed date either.

Can this kind of deadline constraint be set up in MS Project? I see where I can set a hard-and-fast DATE as a deadline, but I don't see a way to make a deadline that is dependent/variable based on the timing of another task in the project.