Unusual is a synonym of Weird. Weird is etymologically related to Worth. Worth is related to Cost. 
Remove is a type of Transfer. Remove is the opposite of Add. Add is related to Operator. 
Unusual <--Synonym--> Weird --EtymologicallyRelatedTo--> Worth <--RelatedTo--> Cost 
Transfer <--IsA-- Remove <--Antonym--> Add <--RelatedTo--> Operator 