Here are some other ways to say no in Welsh, depending on the context:
* "Nac oes" (pronounced "nack ohs") - This means "no there is not" and is used in situations where you are denying the existence of something.
* "Ddim" (pronounced "dim") - This means "not" and is used to negate a verb. For example, "Ddim dw i'n gwybod" means "I don't know".
* "Na, diolch" (pronounced "nah, diolch") - This means "no, thank you".
* "Peidiwch" (pronounced "pay-dee-wch") - This means "don't" and is used as an imperative. For example, "Peidiwch â siarad" means "Don't talk".
It's worth noting that Welsh is a very nuanced language, and the best way to say "no" will depend on the specific situation.