Creating User Generated Content Like Urban Dictionary

The plugins James posted are the right fit for this task. I would definitely go with them. There’s also another way which is called “frontend posting”, and it doesn’t matter what theme you have since it’s also based on plugins.

1) Create a Custom Post Type – you can do this with just code in your functions.php file or you can also do it with a Plugin like https://wordpress.org/plugins/custom-post-type-ui/ (there are lots of Custom Post Type Plugins). You can also use the WordPress default Posts if your site is just a dictionary and you are not using it as a blog.

2) Set up frontend posting for your posts with any of these plugins: https://accesspressthemes.com/blog/top-5-frontend-post-wordpress-plugin/ (there are others out there beyond this list). What these plugins have that’s quite intersting (beyond some features that the above-mention Plugins might not have as they are quite specific) is the ability to link up with the default WordPress posts or a Custom Post Type PLUS some type of moderation, meaning words will not be approved instantly and will require your approval.

Might be worth a shot if you are looking for something custom.