Correct spelling, explanation: separation is a word with a very long history as it already entered English in the 14th century from Old French. The root of the word, however, can be tracked in the Latin language, and more precisely, in the verb separare, which used to mean to pull apart. In modern English separation is a popular noun.

Definition of separation:
1. noun – refers to two things or people that are far away from each other or to a legal arrangement that ends a marriage and is the first step to a divorce;
Every time I go on holiday, the separation from me is a huge trauma for my dog.
It was a great shock for everyone when they announced their separation.

Phrases with separation:
Some interesting phrases with separation include:
1. separation anxiety – usually refers to a child who feels lonely due to the separation from his or her parents;
Separation anxiety is a very common phenomenon when a child starts going to kindergarten.
clear separation – separation which can be easily noticed;
There is a clear separation between a brother and sister once they enter the period of adolescence.

Incorrect spelling, explanation: the only correct spelling of the word is separation. However, a common mistake made by many users of English is to spell it as seperation. It is probably the consequence of the pronunciation, which indeed might suggest that there is -e instead of -a in the middle of the word. Nevertheless, it is wrong so make sure you spell the word as separation.