A disruptor nacelle is a component of Romulan warbirds.

An unusual hybrid starship encountered by the USS Enterprise-D in 2370 included disruptor nacelles from a Romulan warbird. (TNG comic: "Strategy")

The ship in the comic did indeed fire its weapons, presumably disruptors, from its nacelles; whether these structures also function as warp nacelles is unclear, but would seem probable as that is what the identical structures on D'deridex-class warbirds are usually identified as.