Most commonly used as 遛狗 (to walk the dog). It can also mean to stroll casually: 遛遛 or 遛弯儿 (to go around the block).
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An older second-tone reading liú survives only inside the rare bound word 逗遛 (to linger, a variant of 逗留). In all everyday use, including walking a pet and strolling, the character is liù.
Bottom-left walking radical, the side form of 辵 used whenever motion wraps around the bottom-left. It carries the meaning: 遛 is a kind of walking. Same indexing radical as 走, 进, 道.
Inner 留 supplies the sound, liú shifting to liù with the tone change. The 'stay, linger' meaning of 留 also resonates: 遛 is the unhurried walk, the lingering stroll, especially 遛狗 walking the dog or 遛弯儿 taking a turn around the block.
