To make a bubbling or gurgling sound, as water flowing through a narrow passage or liquid being poured.
Likely imitative in origin, related to 'gurgle'; English has many onomatopoetic words for water sounds, all created to phonetically resemble the actual sounds.
Guggle and guggle and gurgle and glugs are all imitative words for the same thing—water noises—and they sound progressively more liquid as you say them, which shows how our brains associate sounds with meanings.
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