Sustentative, also known as sustaining, supporting or nourishing, refers to something that provides sustenance or sustains life. There are numerous synonyms that can be used to describe sustentative, such as nutritive, alimental, fortifying, strengthening, and invigorating. These words all express the concept of providing necessary sustenance or support for something to thrive. Other synonyms include sustaining, maintaining, upholding, and preserving, which emphasize the idea of keeping something viable or enduring. Overall, there are many varied words that can be used to express the meaning of sustentative, all of which convey the vital importance of something that nourishes, supports and sustains life.