Whole Life
All Through Life, Lifelong
noun, の adjective
One life is all you get. It's your whole life. This can also mean all through life, and when it's used as an adjective it means lifelong.
This is a jukugo word that uses the on'yomi readings of the kanji. You didn't learn this reading for 生 though, so here's a mnemonic to help you:
Who has been in charge of you your whole life? The shogun (しょう). He owns everyone and that's how it will stay for your entire life.
主人は一生のパートナーです。
My husband is my partner for life.
色々自分でやらないと、一生自立できないよ。
If you don't do various things yourself, you'll never be independent forever.
あなたは一生、大学一年生でいるつもりですか？
Are you going to be a freshman in college your whole life?