adj

• (slang, of an action or tactic in a game of skill) Underhanded or unfair.
  "the cheap trick of hiding deadly lava under pushable blocks"
• (informal, chiefly derogatory) Stingy; mean; excessively frugal.
  "Insurance is expensive, but don't be so cheap that you risk losing your home because of a fire."
• (finance) Trading at a price level which is low relative to historical trends, a similar asset, or (for derivatives) a theoretical value.
  "The ETF is trading cheap to NAV right now; we can arb this by buying the ETF and selling the underlying constituents."
• (computing) Taking little of system time or resources.
  "the algorithm is cheap to compute"

noun

• (obsolete) Trade; traffic; chaffer; chaffering.
• (obsolete) A market; marketplace.
• (obsolete) Price.
• (obsolete) A low price; a bargain.
  "The sack that thou hast drunk me would have bought me lights as good cheap at the dearest chandler's in Europe."

verb

• (intransitive) To trade; traffic; bargain; chaffer; ask the price of goods; cheapen goods.
• (transitive) To bargain for; chaffer for; ask the price of; offer a price for; cheapen.
• (transitive) To buy; purchase.
• (transitive) To sell.