Slot is a type of Position. Position is the opposite of Absence. Absence is the opposite of Possession. Possession is related to Belong. 
Passage can be used for Read. Passage is related to Narrow. Narrow is a synonym of Contract. 
Slot --IsA--> Position <--Antonym--> Absence <--Antonym--> Possession <--RelatedTo--> Belong 
Read <--UsedFor-- Passage <--RelatedTo--> Narrow <--Synonym--> Contract 