Does "senior thesis" mean the thesis needs for graduation? Is the word "senior thesis" common?

Rebecca

Yes, a "senior thesis" here refers to a "thesis" or a research project that a student completes in their final year or senior year before graduating college. In the United States, completing a "senior thesis" is sometimes a choice, and is not always required to graduate but for certain degrees it is required. In other countries, completing a "senior thesis" is required for graduation.