What is the meaning of spud?

noun

• An edible tuber native to South America; a staple food of Ireland.
  • synonyms: potato, white potato, Irish potato, murphy, tater
• A sharp hand shovel for digging out roots and weeds.
  • synonyms: stump spud

verb

• Initiate drilling operations, as for petroleum.
  • usage: "The well was spudded in April"
• Produce buds, branches, or germinate.
  • usage: "the potatoes sprouted"
  • synonyms: shoot, germinate, pullulate, bourgeon, burgeon forth, sprout