Chef is etymologically related to Cap. Cap is related to Captain. Captain is a different concept from Deputy. 
Sandwich is a type of Food. Food is related to Herb. Herb is related to Alternative. Alternative is similar to Secondary. 
Chef --EtymologicallyRelatedTo--> Cap <--RelatedTo--> Captain <--DistinctFrom--> Deputy 
Sandwich --IsA--> Food <--RelatedTo--> Herb <--RelatedTo--> Alternative <--SimilarTo--> Secondary 