Trabecula laxa is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies.

They form a depressed helicoid spire, whose axis is at right angles to that of the succeeding turns, in the first of which it is about two-thirds immersed.

They are contracted at the sutures, and strongly roundedly shouldered at the summit.

They are marked by sublamellar, flexuose axial ribs, which are only feebly expressed on the first.

The intercostal spaces are about one and one-half times as wide as the ribs, and well impressed.