Something with a little more of the poetic flavor of "turn of phrase" than, say, "forma de hablar" (manner of speaking / figure of speech) or "expresión", that is.
To clarify, I'm thinking of this sense of the expression, which refers to an interesting or compelling phrasing, rather than the person behind it:
turn of phrase (plural turns of phrase)
(idiomatic) An expression which is worded in a distinctive way, especially one which is particularly memorable or artful.
Some examples:
The title is, as the author quickly admits, “a turn of phrase, not the literal truth
[source]
JAVIER SOLANA, the European Union's top foreign-policy honcho, recently offered a neat turn of phrase to explain the importance that Europeans attach to the past. Ponder the phrase “that's history”, and what it implies on either side of the Atlantic, he suggested. When Americans say something is “history”, they mean it is no longer relevant. When Europeans say the same thing, “they usually mean the opposite”.
[source]
President Barack Obama said that “cap and trade” was “just one way of skinning the cat.” It is a common expression, used to imply that there are plenty of ways of doing something. But a closer look at its origins reveals it is a somewhat unsavoury turn of phrase.
[source]
