Among the given options, the misspelled word is "Commisarate."

1. Commisarate: This is the misspelled word. The correct spelling is "Commensurate".

2. Decennial: This is the correctly spelled word. It is an adjective that describes something related to a period of ten years.

3. Nausea: This is the correctly spelled word. It refers to the feeling of sickness or discomfort in the stomach, often leading to the urge to vomit.

4. Curriculum: This is the correctly spelled word. It refers to the subjects or courses of study offered by an educational institution, typically including a set of planned learning experiences and outcomes.