noun
common ragweed; annual ragweed
A common weed in Japan, notorious for causing hay fever. The scientific name is Ambrosia artemisiifolia.
秋になるとブタクサの花粉が飛んで、くしゃみが止まらない。
In autumn, ragweed pollen flies around and I can't stop sneezing.
Hay fever, the allergic condition often caused by ragweed pollen.
Compound of 豚 (buta, 'pig') and 草 (kusa, 'grass/weed'), literally 'pig weed'. The exact origin of the name is uncertain, but it may refer to the plant's use as pig feed or its coarse appearance.