Hurdles are the three foot by two foot blards sheep handles use to force a sheep to
change direction, to make them escaping the sheep dog driving them into enclosure.
Navigate is something done with a boat.
hurdle
n.
5ME hirdel < OE hyrdel < Gmc base *hurd3, wickerwork, hurdle, akin to hyrd, door, Frank *hurda, a pen, fold < IE base *kert3, to plait, twist together > L cratis (see CRATE), Gr kyrtos, bird cage6
1 [Chiefly Brit.] a portable frame made of interlaced twigs, etc., used as a temporary fence or enclosure
2 a kind of frame or sled on which prisoners in England were drawn through the streets to execution
3 any of a series of framelike barriers over which horses or runners must leap in a special race (the hurdles)
4 a difficulty to be overcome; obstacle
vt.
3dled, 3dling
1 to enclose or fence off with hurdles
2 to jump over (a barrier), as in a race
3 to overcome (an obstacle)
hur4dler
n.