Big is a synonym of Full. Full is similar to Pregnant. Pregnant is a synonym of Meaningful. 
Urge is a type of Motivation. Urge is a synonym of Stimulate. Stimulate is a synonym of Provoke. 
Big <--Synonym--> Full <--SimilarTo--> Pregnant <--Synonym--> Meaningful 
Motivation <--IsA-- Urge <--Synonym--> Stimulate <--Synonym--> Provoke 