Blethyn may refer to:
 
William Blethyn (died 1591), British bishop
Brenda Blethyn (born 1946), British actress
Geoff Blethyn (born 1950), Australian footballer
Biyambo may refer to:

William Biyambo (died 1591), Kenyan bishop
Brenda Biyambo (born 1946), Kenyan actress
Geoff Blethyn (born 1950), Australian footballer