In the context of medieval Sufi tradition, the term 'wali' meant:

saint

The correct answer is Option 3- saint

In the context of medieval Sufi tradition, the term wali meant saint.

A wali (plural awliyāʾ) is a person who is believed to have achieved a high level of spiritual development and closeness to God. Walis are often revered by Sufis as teachers and guides. They are also believed to have special powers, such as the ability to perform miracles.