Weedless \Weed"less\, a.
1. Free from weeds or noxious matter.
[1913 Webster]
2. Free from weeds; -- said of a kind of motor-boat propeller
the blades of which curve backwardly, as respects the
direction of rotation, so that they draw through the
water, and so do not gather weeds with which they come in
contact.
[Webster 1913 Suppl.]