n.
 a long difficult journey, especially one made on foot. 
▸S. African a leg or stage of a journey.
v.
 (treks, trekking, trekked)
 go on a trek. 
▸historical, chiefly S. African migrate or journey by ox wagon.
 ▸S. African (of an ox) draw a vehicle or pull a load.
Derivative
  
  Etymology
  C19: from S. Afr. Du. trek (n.), trekken (v.) ‘pull, travel’.