The incorrectly spelled word is "Fasineting."

The correct spelling is "Fascinating," which means extremely interesting or captivating.

The other options, "Occurrence," "Grammatical," and "Professional," are spelled correctly and have the following meanings:

• Occurrence: Refers to an event or incident that happens or takes place.
• Grammatical: Relates to grammar, the rules and structures governing a language.
• Professional: Pertaining to a person engaged in a particular occupation or activity that requires specialized knowledge, training, or skill.