When someone says they "went on the town," it usually means they went out to have a good time and enjoy some nightlife. There are many synonyms for this phrase, depending on what kind of activity was undertaken. Some alternatives to "went on the town" might include "hit the town," "painted the town red," "went out on the town," or "went clubbing." Other phrases might be more specific to the type of activity undertaken, such as "went bar hopping," "went to a concert," or "went to a party." In general, any phrase that suggests going out to enjoy oneself with friends or companions could be used interchangeably with "went on the town".