ἐργαλεῖα

From LSJ

γελᾷ δ' ὁ μωρός, κἄν τι μὴ γέλοιον ᾖ → the fool laughs even when there's nothing to laugh at

Source

Lexicon Thucydideum

instrumenta, tools, 6.44.1, 7.18.4.