Become weak is a phrase that can be described in two ways: LANGUISH and WANE. LANGUISH is an 8-letter word meaning to become weak or feeble, usually due to a lack of energy or enthusiasm. WANE is a 4-letter word meaning to gradually decrease in strength, intensity, or size. Both words are used to describe the same concept, but with different connotations. LANGUISH implies a more gradual decline, while WANE implies a more sudden decrease.