under one's belt

under one's belt  {adv. phr.},  {informal}
1. In your stomach; eaten; or absorbed.
Once he had a good meal under his belt, the man loosened his tie and fell asleep.
Jones is talkative when he has a few drinks under his belt.
2. In your experience, memory or possession; learned or gotten successfully; gained by effort and skill.
Jim has to get a lot of algebra under his belt before the examination.
With three straight victories under their belts, the team went on to win the championship.
Categories: adverb experience informal

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