Synonyms for Watercourse:

n.

feeder, artesian well, rill, beck, geyser, hot spring, tributary. channel, aqueduct, trench. cascade (noun)
flood.
river (noun)
flood, freshet, brook, creek, water, stream, rivulet, river, deluge, torrent.
watercourse (noun)
waterway, stream.
waterway (noun)
channel, aqueduct, stream, brook, creek, river, trench.

Other synonyms:

channel. Other relevant words:
channel, aqueduct, tributary, beck, rill, trench, waterway.

Usage examples for watercourse

  1. Were it not that a shallow watercourse of about fifty miles in width intervenes, the island would be a peninsula. – The Pearl of India by Maturin M. Ballou
  2. Behind and around them were the hills, whose every crevice and hollow was converted into a wild watercourse – The Settler and the Savage by R.M. Ballantyne
  3. In front, beyond a watercourse now dried up, rose the low hill on which stood the Bordj, a huge, square building, with two square towers pierced with loopholes. – The Garden Of Allah by Robert Hichens