verb

• (transitive, ditransitive, intransitive) To transfer goods or provide services in exchange for money.
  "She sold her old car very quickly."
• (ergative) To be sold.
  "This old stock will never sell."
• (transitive) To promote (a product or service) although not being paid in any direct way or at all.
  "Howard: You're gonna feel terrible when I'm in a wheelchair. Which, by the way, would fit easily in the back of this award-winning minivan. Bernadette: Fine, we'll go to the E.R. Just stop selling me on the van. Howard: You're right. It sells itself."
• (transitive) To promote (a particular viewpoint).
  "My boss is very old-fashioned and I'm having a lot of trouble selling the idea of working at home occasionally."

noun

• (figurative, by extension) The promotion of an idea for acceptance.
  "This is going to be a tough sell."
• (colloquial, dated) An imposition, a cheat; a hoax; a disappointment; anything occasioning a loss of pride or dignity.
  ""Of course a miracle may happen, and you may be a great painter, but you must confess the chances are a million to one against it. It'll be an awful sell if at the end you have to acknowledge you've made a hash of it.""

noun

• (obsolete) A seat or stool.
  "The tyrant proud frown’d from his loftie cell, [...]."
• (archaic) A saddle.
  "turning to that place, in which whyleare / He left his loftie steed with golden sell, / And goodly gorgeous barbes, him found not theare [...]."

noun

• (regional, obsolete) A rope (usually for tying up cattle, but can also mean any sort of rope).
  "He picked up the sell from the straw-strewn barn-floor, snelly sneaked up behind her and sleekly slung it around her swire while scryingː "dee, dee ye fooking quhoreǃ"."