I once read a piece of incisive rock criticism that referred to Blue Oyster Cult as “thinking man’s hard rock.” That was long ago, deeper in the past than I care to divulge. But Tuesday’s Artpark performance by the legendary BOC suggested that no better definition of the band has come along since.

Blue Oyster Cult

With Maria Aurigema on Tuesday night as part of the Tuesday in the Park series at Artpark Outdoor Amphitheater.

There were an awful lot of people there, which I realize is not a scientific documentation of head count, but one that will have to suffice. Scattered among those in attendance were more than a few vintage Blue Oyster Cult T-shirts, not all of them worn by the over-25 set. The band’s turn a few years back at the Erie County Fair revealed a burgeoning BOC fan base, at least locally, that was composed mostly of folks commonly (and pejoratively) referred to as “kids,” but in fact, this seemingly equal split between male and female “new” fans appeared to be college-aged. The same was the case with Tuesday’s Artpark crowd.

Opening with “The Red and the Black,” from the band’s second album, “Tyranny and Mutation,” BOC made plain its “thinking man’s hard rock” agenda from the get-go, as guitarist Donald “Buck Dharma” Roeser leaned into the first of what would be many gorgeously meandering, improvised, modal guitar solos. The casual crowd familiar only with the band’s hits had to endure a scorching “Before the Kiss (A Recap)” before the band sauntered into more familiar territory with its ’80s hit, “Burnin’ For You.”

In recent years, the band — which formed in Long Island in the late ’60s, where all the New York natives involved were enrolled in the University at Stony Brook — has revolved around the trio of founding members Buck Dharma, Eric Bloom and Alan Lanier, but this year, Lanier was absent, replaced by second lead guitarist Richie Castellano. It didn’t really alter the band’s sound much; Buck Dharma and Bloom always drove the band, and they did so on Tuesday, though the enrollment of former Ozzy bassist Rudy Sarzo certainly upped the rhythm section thunder quotient.

The band proceeded through some of its more esoteric material, to the delight of the hard-core fans, pulling out one of a few tunes the band coauthored with punk poet Patti Smith in “Shooting Shark”—an extended Buck Dharma solo acted as a thrilling coda to this tune — and dusting down the early beauty “Then Came the Last Days of May” for one of the set’s late highlights.

The final encore of “Hot Rails To Hell” sent the satiated crowd on its way into the beautiful Lewiston evening, and acted as a resounding reminder that Blue Oyster Cult’s music is still cool as all get-out, no matter what age bracket you fall into.