Is there a way to dynamically present single choices from a multiple choice item in another item?

You can use either 'Loop and merge' or 'Form field' question type with carry forward.

Base a loop & merge block on the selected words in the MC question. Pipe the word (${lm://Field/1}) into the question text of a text entry question in the loop & merge block.

I think what you're looking for is a Form question for the definitions that uses Carry forward to populate the choices.
In the example below, I have a multiple-select question, with validation that enforces between 1 and 10 selections. (Yes, they are simple words and not nearly 100 of them, but it's just an example. And if you need to have them select exactly 10, you'd put different validation requirements on Q1.)
Then, after a page break, the Form question uses Carry Forward form fields to populate the options that were selected in Q1.
The result on page 2 would be a table prompting them to define each of the 10 words that were selected in Q1. Note that you'd probably want to play with the settings on the form to ensure the form displays with the amount of space you want to present for definitions:

Thank you very much for your swift answers!
I didn't know about either function before and they both seem to be solutions to my problem. I think that Loop and Merge might be better because I would like to have 10 seperate questions (with page breaks) each asking for one of the 10 selected words. I've set up everything according to an online guide I found but now all 10 questions only show the first of the 10 selected words, not a different one each time.
There surely is a way to get this done, right? I need to explain to Qualtrics that I want the same question answered 10 times for each of the 10 options participants chose in the multiple choice question.

https://community.qualtrics.com/XMcommunity/discussion/comment/49013#Comment_49013You should only have one question in your loop & merge block. It should be something like, "Please define the term ${lm://Field/1}."
If you base your loop & merge on the selected choices in the MC (10 choices), it will loop 10 times.

https://community.qualtrics.com/XMcommunity/discussion/comment/49023#Comment_49023Oh of course, that seems obvious in hindsight - thanks again!
I've got one last question, this time concerning the data structure. I've done a test run and the resulting excel file is huge - it includes every single one of the 100 words as columns and the selected ones contain data (and, because I additionally measure response time, I've got total of 500 columns). So, for each participant, 10x5 columns are filled with their definitions for the particular words they've chosen while the other 90x5 remain empty.
Do you by any chance know of a better way to handle the data later on?

https://community.qualtrics.com/XMcommunity/discussion/comment/49025#Comment_49025It seems you might only care about 1 of the 4 timing fields. If so, you could replace the timing question with a text entry question and some JS that records the response time in that question. That would knock it down to 200 columns.