Correct spelling, explanation: signature is a word of Latin origin as it comes from the Latin verb signare, which could be translated as to mark or to sign. Later, in Medieval Latin, the word had the form of signatura with the meaning of sign manual. Finally, in the 16th century, signature entered English. Today, signature functions only as a noun.

Definition of signature:
1. noun – writing your name by yourself in a way that is characteristic to you, it is usually used to confirm that you’ve written something or agreed to something,
I know her handwriting pretty well and I’m sure it’s not her signature.

Phrases with signature:
A few phrases with signature are as follows:
1. signature dish – the most spectacular dish made by a chef,
He is an excellent chef, but undoubtedly chicken soup is his signature dish.
2. signature tune – a short tune that is played at the beginning or at the end of a program,
I can’t get this signature tune out of my head and I keep singing it all the time.
3. digital signature – putting someone’s name on an electronic document as a way to prove who that person is,
I’m a rather old-fashioned type of person and I don’t trust the idea of a digital signature.

Incorrect spelling, explanation: signature causes some problems when it comes to spelling. One of the most common mistakes is to spell signature as signiture – with the -i letter in the middle instead of an -a letter. The latter form, however, is wrong and the only correct spelling is signature.