What does 单调 (dān diào) mean in English?

Card 188HSK 2010 Level 5188/1311
CARD188
PROGRESS14%
单调
单單
dān diào
monotonous
Click to reveal
← Previous↑ DeckNext →

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