Organic: in agriculture, produced without synthetic chemicals (e.g., organic farming); in chemistry, relating to compounds containing carbon (organic compounds).
有機野菜を買って、サラダに使った。
I bought organic vegetables and used them in a salad.
有機化学の授業で新しい反応を学んだ。
I learned a new reaction in organic chemistry class.
有機栽培の農家は化学肥料を極力使わない。
Organic farms avoid using chemical fertilizers as much as possible.