To make spitting or explosive sounds while talking, or to speak in a confused or angry way with interrupted words.
From Dutch 'sputteren,' an imitative word meant to sound like the action it describes. Imitative words like this often enter languages from neighboring cultures.
The word 'splutter' is onomatopoeia—it literally sounds like what it means—and linguists think imitative words like this are among the oldest types of words in any language because they directly copy sounds!
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