Subspace oscillation was a periodic variance in subspace. Subspace oscillations were observable by 24th century Federation sensors. They could cause minor gravimetric vibrations.

Subspace oscillations were one of the effects observed in subspace disruptions. When Deep Space 9 was threatened by a nearby subspace rupture around stardate 46853, the station's perimeter sensors picked up subspace oscillations. These oscillations caused the station to vibrate. (DS9: "If Wishes Were Horses")