There are several synonyms for the phrase "mens rooms." Some of the most common include "men's restroom," "men's bathroom," "men's lavatory," and "men's washroom." These terms are often used interchangeably and refer to the same space within a public or private facility where men can use the restroom facilities and wash their hands. Other less used synonyms for men's rooms include "gents' toilets," "male facilities," and "masculine restrooms." It is essential to note that some of these synonyms may be more appropriate in certain contexts than others, depending on the location and the level of formality of the facility.