horsefly, gadfly
蝱 centers on a biting, blood-sucking fly that pesters livestock: a horsefly or gadfly.
蝱 combines 亡 (likely a phonetic component) with 䖵 (two insects), suggesting a type of insect. The exact historical development is uncertain.
The top 亡 looks like a lid or cover, and the bottom 䖵 is a pair of insects. Imagine a swarm of horseflies trapped under a lid, buzzing angrily.
For ボウ, picture a bow (as in bow and arrow) used to swat away a persistent horsefly: bow -> ボウ, and the fly dodges the bow.