The word "excel" has multiple meanings, depending on its context.
1) In a general sense, it can refer to doing something exceptionally well or achieving high standards in a particular field. For example, "She excels at playing the piano."
2) It can also be used as a verb meaning to surpass or outdo others in some capacity such as knowledge, skill, ability, etc. For instance, "He always tries to excel his peers by working harder and longer hours."
3) In its most common usage, "excel" is an abbreviation for the Microsoft Excel, which is a spreadsheet software used for data organization, analysis, and visualization.