not know B from a battledore(redirected from battledore)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to battledore: battledore and shuttlecock, stinkhorn
not know B from a battledore
To be really stupid, or perhaps illiterate. The now-outdated term "battledore" was often used in reference to a children's primer. It was likely used in this phrase simply for the sake of alliteration. How do you manage to burn pasta? It's like you don't know B from a battledore.