How do you spell sertint?

"Sertint" is not a standard English word. It's likely a misspelling of a word like:

* Certainty: meaning a firm conviction or belief.

* Sentiment: meaning a feeling or opinion.

* Certain: meaning sure or definite.

* Tint: meaning a slight shade of color.

To be sure, I need more context. Can you provide more information about how you encountered this word?