vi·tal/`vaɪtḷ; ˈvaɪtl/ adj 1 extremely important or necessary 极其重要的; 必不可少的: His evidence was vital to the defence case. 他的证词对辩方的论据非常重要。 It is absolutely vital that you do as I say. 你一定要照我说的话去做。 2 having a lot of energy, in a way that seems attractive 精力充沛的,生气勃勃的