Firm is a synonym of Solid. Solid is similar to Dry. Dry is related to Like. Like is related to Web. 
Car have Engine. Indicator is part of Car. Indicator is a synonym of Index. 
Firm <--Synonym--> Solid <--SimilarTo--> Dry <--RelatedTo--> Like <--RelatedTo--> Web 
Engine <--HasA-- Car <--PartOf-- Indicator <--Synonym--> Index 