Silence is the opposite of Song. Song is related to Composition. 
Grass is related to Pitch. Strike is a type of Pitch. Butt is a type of Strike. Butt is a synonym of Target. 
Silence <--Antonym--> Song <--RelatedTo--> Composition 
Grass <--RelatedTo--> Pitch <--IsA-- Strike <--IsA-- Butt <--Synonym--> Target 