Definitions
Wholly is an adverb that means entirely or completely.
Example
I am wholly committed to this project.
Example
The idea is wholly impractical.
Holy is an adjective that refers to something that is sacred or related to a deity or religion.
Example
The holy book of Islam is the Quran.
Example
The temple is considered a holy place by many people.
Tips To Remember the Differences
Here are a few tips to easily distinguish the difference between these words while keeping in mind the description we've provided:
To remember the difference between these two words, you can associate wholly with 'completely' and holy with 'sacred'.
Remember this!
Remember, wholly means 'completely', while holy means 'sacred'.