Legal is related to Law. Lawsuit is derived from Law. Lawsuit is related to Case. Case is related to Brief. 
Mate is a synonym of Sir. Sir is related to Dear. Dear is related to Spouse. Spouse is etymologically related to Sponsor. 
Legal <--RelatedTo--> Law <--DerivedFrom-- Lawsuit <--RelatedTo--> Case <--RelatedTo--> Brief 
Mate <--Synonym--> Sir <--RelatedTo--> Dear <--RelatedTo--> Spouse --EtymologicallyRelatedTo--> Sponsor 