I remember that there was a word that meant being knowledgeable about many words, but I've forgotten what the word was.
This thread may be of use. Here are some of the words suggested from it: "lexicomane, sesquipedalian, vocabularian, logophile". Their specific definitions are listed in the thread.
The OED has verbalist:
- One who is skilled in the use or knowledge of words.
1794 T. Taylor tr. Pausanias Descr. Greece I. Pref. p. viii, His meaning is, frequently, on this account, inaccessible to the most consummate verbalists.
1822 T. Taylor tr. Apuleius Metamorphosis 351 This blunder of the editor, who was otherwise a good verbalist, is a deplorable specimen of ignorance in things of the greatest importance.
1860–1 Philol. Soc. Trans. 164 The opinion of the best English verbalist I ever knew.