Variable is a synonym of Flexible. Flexible is related to Paper. Paper is related to Page. Page is a type of Leaf. 
Mine is related to Collection. Collection is related to Galaxy. Galaxy is related to Formation. Formation is related to Rock. 
Variable <--Synonym--> Flexible <--RelatedTo--> Paper <--RelatedTo--> Page --IsA--> Leaf 
Mine <--RelatedTo--> Collection <--RelatedTo--> Galaxy <--RelatedTo--> Formation <--RelatedTo--> Rock 