Cries uncontrollably with loud sobs, or the plural noun referring to the fat layer of whales and seals.
From Middle English 'blubber,' possibly from Dutch 'blubber' or onomatopoetic origin mimicking crying sounds. The whale fat meaning emerged in the 16th century from the sound of it bubbling when rendered.
Whalers gave whale fat the name 'blubber' partly because it made a blubbering, bubbling sound when heated to extract oil—the same word used for crying because both involve messy, uncontrolled sounds!
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