na-adjective, adverb
Kansai dialect word meaning a large amount or number; used as an adverb or adjectival noun. In standard Japanese, たくさん is the equivalent.
ぎょうさん食べてな。
Eat plenty, okay?
今日は人がぎょうさんおるなあ
There sure are a lot of people today.
na-adjective
exaggerated; grandiose
Describes something overstated or blown out of proportion. This sense is not dialect-specific and can appear in standard Japanese, though it is somewhat literary or old-fashioned.
彼の話はいつもぎょうさんだ。
His stories are always exaggerated.
そんなぎょうさんな表現は必要ない。
Such grandiose expressions are unnecessary.
The origin is uncertain. The kanji 仰山 are ateji; the word likely derives from a dialectal expression in the Kansai region.