Loanword prefix used to intensify adjectives or nouns, similar to 'ultra-' or 'super-' in English. Common in product names, casual emphasis, and compounds like ウルトラマン.
This smartphone is ultra high-performance.
ウルトラマンは日本の有名なヒーローだ。
Ultraman is a famous Japanese hero.
This puzzle is ultra difficult.
I heard this store is having an 'ultra sale' this weekend.