verb

• (transitive) To make something fall; especially to chop down a tree.
  "Stand, or I'll fell thee down."
• (transitive) To strike down, kill, destroy.
  "Gahan, horrified, saw the latter's head topple from its body, saw the body stagger and fall to the ground. ... The creature that had felled its companion was dashing madly in the direction of the hill upon which he was hidden, it dodged one of the workers that sought to seize it. … Then it was that Gahan's eyes chanced to return to the figure of the creature the fugitive had felled."
• (sewing) To stitch down a protruding flap of fabric, as a seam allowance, or pleat.
  "To fell seam allowances, catch the lining underneath before emerging 1/4" (6mm) ahead, and 1/8" (3mm) to 1/4" (6mm) into the seam allowance."

noun

• (textiles) The end of a web, formed by the last thread of the weft.

noun

• (archaic outside Northern England, Scotland) A rocky ridge or chain of mountains, particularly in the British Isles or Fennoscandia.
  "Every now and then the sea calls some farmer or shepherd, and the restless drop in his veins gives him no peace till he has found his way over the hills and fells to the port of Whitehaven, and gone back to the cradling bosom that rocked his ancestors."
• (archaic outside Northern England, Scotland) A wild field or upland moor.
  "As over Holt and Heath, as thorough Frith and Fell;"

adj

• (UK dialectal, Scotland) Strong and fiery; biting; keen; sharp; pungent
• (UK dialectal, Scotland) Very large; huge.
• (obsolete) Eager; earnest; intent.
  "I am so fell to my business."