Someone who writes or composes something, especially a literary work; an author.
From 'pen' (Latin 'penna' meaning feather, since ancient pens were feathers) combined with '-er' (suffix meaning one who does). It's an older term for writer, less common in modern English.
A 'penner' literally refers to someone who uses a pen made from feathers—quill pens—and the word is so old that it reminds us pens used to be actual dead bird feathers shaped into writing tools!
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