To cry or weep, especially in an uncontrolled or pathetic way; to sob.
Onomatopoeia possibly related to 'blubber' or from the sound of crying. British informal, dating to at least the 19th century.
British schoolchildren have used 'don't blub' for generations—the word captures something that 'cry' doesn't, a specific kind of uncontrolled, messy, embarrassing weeping.
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