Without vigor is a term used to describe a lack of energy or enthusiasm. Limply, with six letters, is an adverb meaning in a weak or relaxed manner. Wanly, with five letters, is an adverb meaning in a pale or feeble way. Feebly, with six letters, is an adverb meaning in a weak or feeble manner. Sluggishly, with ten letters, is an adverb meaning in a slow and lazy manner. All of these words describe a lack of vigor or energy.