noun-modifying (irregular)
decaffeinated; caffeine-free
Wasei-eigo from English 'caffeine-less'. Used prenominally to describe drinks or products without caffeine.
wasei-eigo (Japanese-coined English), from caffeine-less
カフェインレスのコーヒーをください。
I'll have a decaffeinated coffee, please.
最近はカフェインレスのお茶も人気がある。
Caffeine-free tea has also become popular recently.