Correct spelling, explanation: the word toilet first entered English in the middle of the 16th century. The origin of the word is French toilette and it was used to name a wrapper for clothes. It was not until the 20th century before toilet began to have the meaning that we know in contemporary English.

Definition of toilet:
1. noun – refers to a room with a toilet, an oval device that we sit on while in the bathroom, or to the process of washing yourself and getting ready:
The house has a beautiful and well-equipped toilet.
The toilet seat was broken and dirty – it was really disgusting.
Before her wedding day, she spent almost five hours over her toilet.

Collocations and idioms with toilet:
Some typical collocations and phrases include: down the toilet (which means something is wasted), toilet bowl, toilet roll:
All the money went down the toilet due to his gambling problem.
The toilet bowl in the restaurant was really ugly and not very clean.
There are two toilet rolls in the bathroom, but if you need more, just let me know.

Incorrect spelling, explanation: the word toilet has quite a simple spelling and pronunciation, but still many English users make a mistake while writing it. Namely, instead of toilet, they spell the word as toliet, which is the wrong form so do not use it.