eighty-sixth I. \| ̷ ̷ ̷ ̷| ̷ ̷\adjective 1.: being number 86 in a countable series < the eighty-sixth day > — see number table 2.: being one of 86 equal parts into which something is divisible < an eighty-sixth share of the money > II. noun 1.: number 86 in a countable series 2.: the quotient of a unit divided by 86 : one of 86 equal parts of something < one eighty-sixth of the total >