What does 兢兢业业 (jīng jīng yè yè) mean in English?

Card 1011HSK 2010 Level 61011/2512
CARD1011
PROGRESS40%
兢兢业业
兢兢業業
jīng jīng yè yè
cautious and conscientious

Reveal: Click/Space/Enter/↑↓/w/s/j/kNavigate: ←→/h/l/a/d