Definition of dog cheap in US English:

dog cheap

adjective

archaic
  • Extremely cheap.

adverb

archaic
  • At a very low or contemptible price.

Origin

Early 16th century. From dog + cheap; compare uses at dog, unless originally with allusion to dogs being cheap to purchase; perhaps compare also good cheap, although folk-etymological alteration of that compound seems improbable.

Pronunciation

dog cheap

/ˈdɒɡ ˌtʃiːp/