Atmospheric probe

From Memory Alpha, the free Star Trek reference.

Atmospheric probes are Starfleet probes carried aboard the USS Defiant.

In 2372, the Defiant had two such probes aboard. In that year, Benjamin Sisko had Miles O'Brien equip them with warheads from the quantum torpedoes to be used against two Jem'Hadar fighters. The probes were also programmmed to home in on the first metallic signature they detected. The first probe was successful in destroying one of the Jem'Hadar ships, but not before the Dominion vessel did serious damage to the Defiant.

Worf later had the second atmospheric probe emit an echolocation tetryon pulse just like the Defiant had been doing. The Jem'Hadar focused on it, believing it to be the Defiant, but distracted them long enough for the Defiant to destroy them. (DS9: "Starship Down")