穏健[onken] quiet
頑健[ganken] robust health
強健[kyouken] robust health
健か[shitataka] determined
健やか[sukoyaka] vigorous

健胃剤[kenizai] stomach medicine
健胃錠[kenijou] stomach tablets
健気[kenage] brave
健脚[kenkyaku] good walker
健脚家[kenkyakuka] good walker

健啖[kentan] gluttony
健啖家[kentanka] glutton
啖呵[tanka] caustic words

啖う[kuu] to eat
啖呵を切る[tankawokiru] to speak sharply (e.g. during a heated discussion or argument)