adverb taking the 'to' particle
Mimetic adverb describing the sound of water mixing with air, such as water welling up, pouring, draining, or gushing. Used with と.
排水口から水がごぼごぼと流れ出た。
Water gurgled out of the drain.
やかんのお湯がごぼごぼと沸いている。
The water in the kettle is bubbling and boiling.