βάλανος

1. an acorn , Lat. glans, the fruit of the φηγός, given to swine, (Odyssey by Homer):—; any similar fruit, the date , (Herdotus Historicus)

2. from similarity of shape, an iron peg, a bolt-pin , Lat. pessulus, passed through the wooden bar ( μοχλός) into the door-post, so that the bar could not be removed till the pin was taken out with a hook ( βαλανάγρα), (Aristophanes Comicus) (ML)