The Italian adjective "insulsi" (plural of "insulso") means silly, dull, bland, or idiotic. It is often used to describe things lacking flavor or interest, including certain phrases which can be referred to as "insulsi come certe frasi," meaning phrases that are bland or banal. Essentially, "insulsi" describes something that is weak, uninteresting, or lacking wit or substance, as in the case of certain trivial or empty phrases.

So, the phrase "insulsi come certe frasi" translates to "silly/bland like certain phrases," indicating that those phrases are unimpressive, dull, or banal in nature.

This word carries the connotation of something "unsalted" or tasteless, both literally and figuratively, referring to something without zest or impact.