Correct spelling, it is a combination of verb explain (to describe something, to give information about it, so then it is easily understandable), and a suffix -ation, which main role is to create a noun from a verb or adjective. But to make English pronunciation easier, the i in the verb is omitted and the correct spelling is explanation.

Definition of explanation:
noun, the specific, or details that someone gives you, so you can understand what he is talking about and everything is clear
I don’t need your explanation to understand what I see.
One day, he just moved out, without any explanation.

Incorrect spelling, this word was created by taking a verb explain (to give knowledge about something, to make it clear) and a suffix -ation that we use to form a noun- but we also can’t forget about the fact, that we omit one i to create correct form – explanation.

Incorrect spelling

Incorrect spelling

Incorrect spelling

Incorrect spelling