practise is a verb meaning to perform an activity or exercise repeatedly to improve or maintain proficiency.
In British English, practise is the verb form, while "practice" is the noun. In American English, "practice" is used for both.
Other meanings of practise include:
1. To carry out or perform (a particular activity, method, or custom) habitually or regularly
2. To work at (a profession or occupation)
3. To observe the teachings and rules of (a religion)