no saber hacer la o con un canuto

Spanish

Etymology

Literally, “not know how to make an 'O' with a tube”.

Verb

no saber hacer la o con un canuto (first-person singular present no sé hacer la o con un canuto, first-person singular preterite no supe hacer la o con un canuto, past participle no sabido hacer la o con un canuto)

1. (idiomatic) to not know one's head from a hole in the ground
2. (idiomatic) couldn't organise a piss-up in a brewery