An idiom is an expression that is not meant to be understood literally. Here are two English examples:
“He really threw me a curve when on our first date he asked if I could pay for the dinner.” Some couples just agree to go dutch.
More English idioms are here. Here is a list of some Greek idioms:
δια τουτο – for this reason
εκ τουτου – by this
ο εχων – one who has
εν ποια – by what
δια παντος – always
δια τι – why?
εις τον αιωνα – forever
