A new NBC sitcom, “Everything’s Relative,” is appropriately named.

Relative to the evening news, it’s a laugh riot. But relative to a vast majority of the network sitcoms, it’s remarkably laugh-free.

In “Everything’s Relative,” debuting at 9:30 tonight, Kevin Rahm plays Leo, a young comedy writer who’s being smothered by his overbearing family. There’s his eccentric father, Jake, who considers himself quite the ladies’ man. There’s his mother, Mickey, a clinical psychiatrist who’s still obsessed with Jake, even after being divorced for 20 years. Then there’s his surgeon brother, Marty, who is about to get married for the third time.

Here are examples of the humor in the first episode. Jake sets up Leo, whose relationship recently fell apart, with a woman who’s attracted to Jake. Mickey is contemplating moving into the house right across the street from Jake. Marty is concerned that Jake is throwing him an engagement party in lieu of a wedding gift, and he wants merchandise instead. Oh, my sides hurt.

Leo must be quite a good comedy writer, although there’s precious little evidence of this. After all, Mickey repeatedly says, “You always make me laugh.” That makes one of us.

Rahm is the colorless, formless nucleus around whom a group of whackos orbits. Jeffrey Tambor, so good as the obsequious Hank Kingsley on “The Larry Sanders Show,” deftly plays the overbearing Jake. Jill Clayburgh, seen briefly as the mother in “Trinity,” makes the most out of that TV stereotype, the meddling but well-meaning mom. Eric Schaeffer (“My Life’s in Turnaround”) is annoying as the self-absorbed Marty.

In a stroke of scheduling prowess, NBC has managed to replace one of the season’s wittiest new sitcoms, “Will & Grace” (which moves to 8:30 p.m. Thursdays) with one of the most witless. Don’t waste your time. Turn over to “Sports Night” on ABC instead.