—n.
1 (usu. in pl.) an impediment to free movement; a hindrance (the trammels of domesticity).
2 a triple drag-net for fish, which are trapped in a pocket formed when they attempt to swim through.
3 an instrument for drawing ellipses etc. with a bar sliding in upright grooves.
4 a beam-compass.
5 US a hook in a fireplace for a kettle etc.
—v.tr. (trammelled, trammelling; US trammeled, trammeling) confine or hamper with or as if with trammels.
Etymology: in sense 'net' ME f. OF tramail f. med.L tramaculum, tremaculum, perh. formed as TRI- + macula (MAIL(2)): later history uncert.
Useful english dictionary. 2012.