How do you say great in Welsh?

The most common way to say "great" in Welsh is "gwych" (pronounced "gwich").

Here are some other options, depending on the context:

* "rhyfeddol" (pronounced "rhi-ved-dol") - means "wonderful" or "amazing"

* "rhagorol" (pronounced "ra-gor-ol") - means "excellent" or "outstanding"

* "ardderchog" (pronounced "ar-der-kog") - means "magnificent" or "splendid"

The best option for you will depend on the specific situation.