Product is related to Soap. Soap is related to Dish. 
Piano is similar to Organ. Organ is related to Ear. Ear is related to Sense. Sense is related to Logic. 
Product <--RelatedTo--> Soap <--RelatedTo--> Dish 
Piano <--SimilarTo--> Organ <--RelatedTo--> Ear <--RelatedTo--> Sense <--RelatedTo--> Logic 