Past tense of gulp; to swallow quickly and noisily or in large amounts.
From 'gulp,' which likely comes from Dutch 'gulpen' or imitative origins, as the word's sound resembles the actual act of swallowing audibly.
The word 'gulp' is onomatopoeia—it literally sounds like the action it describes, which is why it appears in cartoons and comics as a sound effect, and why people instinctively understand what 'gulped' means even if they've never heard the word before.
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