When it comes to describing people or things as second-rate, there are a variety of synonyms that can be used to convey a lack of quality or excellence. Some common alternatives to "second rater" include "mediocre," "subpar," "inferior," "middling," "ordinary," "average," "not up to par," "below standard," "unexceptional," "unsatisfactory," "half-baked," and "so-so." Each of these words carries its own nuances and connotations, but all can be used to indicate that something or someone falls short of expectations or the desired level of excellence. So whether you're critiquing a book, movie, or person, there are plenty of synonyms at your disposal to help describe shortcomings and disappointments.