Wordsmith
Collect 50 percent of all words.

Once you acquire Grimoire Weiss, you will have a small chance of obtaining words by defeating enemies that will improve certain attributes, such as strength and item drop rate. Your word percentage will carry over to New Game+

To view your current word percentage, view the word list under the Memo heading in Grimoire Weiss. You can access Grimoire Weiss by pressing [Start Button] and then [D-pad Down]

You can also apply words you have collected to weapons and/or magic by accessing Word List Edit within Grimoire Weiss, selecting what magic ability or weapon you wish to add the word too and choosing upto three different words.

Glitched?
Some users have reported this trophy unlocking, despite have 50% or more total words obtained. Personally, the trophy unlocked for me at 50%, but not as soon as i hit 50%. If it fails to unlock for you once you get to 51%, load an older save and hope it pops this time.