This is the 18070th most frequent Polish word.
życiowa
"Życiowa" means "life-related" or "pertaining to life."
In this sentence, 'życiowym' is an adjective derived from the noun 'życie' (life) and means 'lifetime' or 'life-related'. Here, it modifies 'sukcesem' (success), to convey that the achievement is of major significance in one's life.
Zdobycie tej pracy było dla mnie życiowym sukcesem.
Getting this job was a lifetime achievement for me.
Here, 'życiowo' is the adverbial form of 'życiowa', used to describe being competent or resourceful in practical matters or general living situations.
Moja przyjaciółka jest bardzo życiowo zaradna.
My friend is very resourceful in life.
In this sentence, 'życiowe' (vital, life-related) modifies 'pytanie' (question) to suggest that the query holds significant importance and pertains to fundamental matters in life.