Logolepsy

n. A severe fascination or obsession with words

Pretty straighforward

Examples:

Thanks to the magic of teleconferencing, often the format for a given show is call-in, and the phones and airwaves crackle with logolepsy.
— Richard Lederer, A Man of My Words (2003)

A case of logolepsy is easily distinguished from the perfectly sane mood which demands and imperiosly seizes the pregnant sign, and makes it the exponent of a hidden power.
— Maurice Thompson, My winter garden: a nature-lover under southern skies (1900)

Etymology:

Logos is Greek for “word”, -lepsy is Greek, “to seize”