sixty-third adjective 1noun 1forms 1 adjective1 •The ordinal form of the number sixty-three, describing a person or thing in position number 63 of a sequence.The answer appears on the sixty-third page of the book.She finished sixty-third in the race. noun1 •One of sixty-three equal parts of a whole.A sixty-third of 1260 is 20. formssixty-thirds
