Wahi or Wahee وحي: revelation through arch-angel Gabriel or a divine inspiration
Wajib واجب: compulsory, obligatory, binding
Wakil or Wakeel وكيل: a person who is an authorized representative or proxy; agent. It can also mean lawyer in Urdu.
Wali or Walee ولي: person to whom wilayat ولايه is obligatory. A wali والي, however, is a governor appointed by a Muslim ruler of a higher authority (such as a caliph, sultan, etc.), legal guardian, friend or protector, someone who is supposed to look after your interest
Walima وليمه: post-wedding feast, reception.
Wasi وصي: successor to a prophet; guardian, protector, custodian
Wilayat ولايه: a binding supreme authority that combines both temporal and religious powers
Wial وصال: fasting the last day of every lunar calendar month
Wudu or Wuzu وضوء: a purification (ablution) which must be performed before the salat or the recitation of the Qur'an