Abstract is similar to Theoretical. Theoretical is the opposite of Actual. Actual is the opposite of Estimated. 
Wolf is related to Sheep. Sheep is related to Hair. Hair is related to Doll. Doll is related to Do. 
Abstract <--SimilarTo--> Theoretical <--Antonym--> Actual <--Antonym--> Estimated 
Wolf <--RelatedTo--> Sheep <--RelatedTo--> Hair <--RelatedTo--> Doll <--RelatedTo--> Do 