winnow, fan
簸 centers on separating grain from chaff by tossing it in the air, typically with a flat basket: winnowing or fanning.
簸 combines 竹 (bamboo) with 其 (winnowing basket) and 皮 (skin/husk), suggesting a bamboo winnowing fan that separates husks. The exact historical development is uncertain, but the component combination fits the meaning.
The top 竹 is bamboo, often used to make winnowing fans. Below, 其 resembles a basket and 皮 suggests skin or husks. Picture a bamboo fan tossing grain so the light husks (皮) fly away.
For ハ, imagine the sound of a winnowing fan: 'ha!' as you exhale sharply to blow away the chaff. The breathy 'ha' cues ハ while you fan the grain.
to winnow (grain)