There was a time when a Jennifer Lopez joke was a cultural barometer: What to make fun of next — the legendary posterior, the whirlwind romances, the disyllabic nickname that caught on faster than any of her “songs” — was like a measurement of America’s insatiable appetite for celebrity schlock. It’s no wonder that the backbeat to “Love Don’t Cost a Thing,” one of her early smashes, was a circus drum with bigtop flourishes. She was a queen of the showbiz circus.

But, alas, how things change. The former diva is practically embracing her newfound has-been status. She long ago crossed “actress” off her resume. If her new album “Rebirth” is any indication, she’ll soon be axing “singer” as well. The album is a feeble attempt to cash in on the success of her biggest hits — which, back in 2001, were actually fairly fresh. Here, they are reborn as tepid, dull rehash.

Take this poetry from “This Is Me,” with lyrics by Lopez: “How can you say that you love me yet to leave you alone/ You said these walls were here to protect us but it’s still not a home.” Hard to believe, but they’re still not as wretched as this steaming hunk of stilted verse from “Hold You Down,” written by one of her producers: “Watch me paint a picture so perfect, quite possibly/ The realest fresher from BX to South Beach/ I’ma always hold you down.” This swill is actually printed in the CD booklet, as if its writers didn’t want to forget about it as soon as possible. They’re happily sandwiched between some legitimately seductive photos of the pop star (unbelievable that someone that sexy could sing a love song so sexless.)

Way back when, Lopez’s number-one singles with Murder Inc. featured lush production and hot rappers, which gave her a healthy dose of street cred (or so she assured us) in addition to mainstream success. In some dramatic marketing misstep, she’s backed down from the hip-hop angle that pushed her envelope — where’s Puff “P. Diddy” Daddy when you need him? The album’s first single, “Get Right,” effuses a too-sparse-to-freak beat with a grating horn sample. Apparently the beat was rejected from Usher’s latest album before it found its way to Lopez’s, which just might explain why it sucks. Maybe a Ja Rule or two would liven things up — but instead, a laughably out-of-place young girl closes the track, chiming in over Lopez’s chorus. As a testament to its un-catchiness, the song hasn’t rocketed up the charts like most of J.Lo’s singles: On the eve of her album release, it hasn’t even cracked Billboard’s top 10, and is already falling down the chart.

The second track, “Step Into My World,” has a much better chance at some major airplay. The song, produced by pop-rap impresario (and Destiny’s Child Svengali) Rodney Jerkins, layers a sensuous, Indian-tinged drum beat against some lush and lovely sound wave effects, while an understated Spanish guitar and mid-tempo hand claps add richness and dimension. The only problem is the singer — couldn’t they have found a diva better than Jennifer Lopez? The track would really take off in the hands of someone who can sound as hot as she looks. And, really, would anyone mind if Beyonce had filled in for the singing on this album?

A few other tracks deserve mentioning, at least as a warning so that no one else ever has to listen to them. “Hold You Down” already got its shout-out, but it’s really so incredibly bad that it gets another drubbing. Check out this stinker: “Like green is to autumn, some things must stay/ This industry, yeah I fought ’em, made me this way.” In the same vein, the limp ’80’s workout “Cherry Pie” features the title phrase as a vivid and pointless metaphor for love, sex, or something: “I can be your cherry pie/ And you can be my cream on top,” Lopez sings (not once, but twice, just in case someone missed it the first time through). Lucky Marc Anthony!

The most interesting song on “Rebirth” would have to be “Still Around,” mostly because of what it avoids rather than what it includes. Instead of a heated invective against the naysayers who predicted no one would be listening after her first few hits, as the title suggests, it’s another slushy slog through a vague and aimless relationship. Perhaps Ms. Lopez has finally realized that the naysayers were right. A couple J.Lo end-of-career puns come to mind, but honestly, who cares anymore?