noun
Hosta montana; a species of plantain lily
A perennial plant native to Japan, known for its large, broad leaves and pale purple flowers. Often grown as an ornamental shade plant.
庭の日陰にオオバギボウシを植えた。
I planted Hosta montana in the shady part of the garden.
オオバギボウシの花が咲き始めた。
The Hosta montana flowers have started to bloom.
ギボウシ is the general term for hosta or plantain lily; オオバギボウシ specifies the large-leaved species Hosta montana.
From 大葉 (おおば, 'large leaf') + 擬宝珠 (ぎぼうし, 'hosta'). The name describes the plant's large leaves.