What does 亩 (mǔ) mean in English?

Card 57NPCR Level 5657/108
CARD57
PROGRESS53%
mu (a chinese unit of area equal to 1/15 of a hectare or 1/6 of an acre)(Measure Word)

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