Decline is a type of Decrease. Decrease is a synonym of Lower. Lower is related to Bishop. Bishop is a different concept from King. 
Age is related to Adult. Bull is a type of Adult. 
Decline --IsA--> Decrease <--Synonym--> Lower <--RelatedTo--> Bishop <--DistinctFrom--> King 
Age <--RelatedTo--> Adult <--IsA-- Bull 