Custom is a synonym of Use. Use is a synonym of Treatment. Treatment is a synonym of Deal. Deal is related to Play. 
Poet is related to Intellectual. Intellectual is related to Writing. Writing is related to Number. 
Custom <--Synonym--> Use <--Synonym--> Treatment <--Synonym--> Deal <--RelatedTo--> Play 
Poet <--RelatedTo--> Intellectual <--RelatedTo--> Writing <--RelatedTo--> Number 