Attractive force? (7)
'attractive force' is the definition.
(gravity is a kind of attractive force)
This is all the clue.
(Other definitions for gravity that I've seen before include "Pulling power" , "Importance; a natural force" , "The force of attraction between masses in the universe" , "Great seriousness" , "weight" .)
(Other definitions for glamour that I've seen before include "Beauty created by clothes and make-up" , "Voluptuous allure" , "Fascinating beauty" , "Charm and allure" , "Groomed beauty, allure" .)