What is the definition of to coin a phrase?

To coin a phrase ( or a term) is to invent a figure of speech. Finley Peter Dunne was the first person to call a left-handed pitcher a "southpaw," and so he is said to have coined the term.
To coin a phrase ( or a term) is to invent a figure of speech. Finley Peter Dunne was the first person to call a left-handed pitcher a "southpaw," and so he is said to have coined the term.