In Norse mythology, the watchman god who guards the rainbow bridge Bifrost and is said to have nine mothers and exceptional hearing.
From Old Norse 'Heimdallr,' possibly combining 'heimr' (world) and 'dallr' (doll or dear, though etymology is debated). The name appears in the Poetic Edda, one of the primary sources for Norse mythology.
Heimdal could hear grass growing and sheep's wool being shorn from impossibly far away—basically he was the ancient Norse version of surveillance technology, and he never slept, making him possibly the most paranoid deity ever created.
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