Homographs are words spelled alike but with different meanings and usually with different pronunciations (lead, v. [LEED], meaning “to conduct,” and lead, n. [LED], the name of the metal).
Homophones are words pronounced alike but different in spelling and meaning (to, two, and too).
Homonyms, a more general term, are words spelled or pronounced alike but having different meanings: soar and sore are one sort of homonym; gore, meaning “the tapered piece of cloth in a skirt,” and gore, meaning “blood,” are examples of another sort. Bow, v., “to bend at the waist,” and bow, n., “the front end of a boat,” are homonyms, and some would add the differently pronounced bow, meaning variously “the weapon for shooting arrows,” “the decorative knot used in hair ribbons and bow ties,” “the long, slender rod strung with horsehairs used to play stringed instruments.”
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-willie