Encounter is a synonym of Action. Action is related to Fall. 
Relationship is related to Son. Son is the opposite of Comparison. Confrontation is a type of Comparison. Confrontation is derived from Confront. 
Encounter <--Synonym--> Action <--RelatedTo--> Fall 
Relationship <--RelatedTo--> Son <--Antonym--> Comparison <--IsA-- Confrontation --DerivedFrom--> Confront 