green mandarin; green-skinned mandarin orange
Refers to a type of mandarin orange that can be eaten while the skin is still green; not simply an unripe orange.
青蜜柑は皮が緑色でも甘くて美味しい。
Green mandarins are sweet and delicious even though the skin is green.
この時期になると青蜜柑が出回り始める。
Around this time of year, green mandarins start appearing in stores.
Compound of 青 (ao, 'green') and 蜜柑 (mikan, 'mandarin orange'), literally 'green mandarin'.