"Beat one's gums" is a colloquial phrase that means to talk excessively or chatter without making much sense. There are several synonyms for this phrase that can be used to express the same or similar meaning. Some of these synonyms include "jawing," "blathering," "rambling," "babbling," "yakking," "prattling," "jibber-jabbering," "nattering," and "driveling." Each of these words implies that one is talking too much or without purpose. These synonyms can be used interchangeably to convey the idea that someone is speaking incessantly or overly elongating a conversation without any substantial contribution.