1) Xctotheromans 1) Advanced age 2) Age of a young nonagenarian 3) An age of high speed 4) Being ten more than eighty 5) Cardinal 6) Degrees in a right angle 7) Doing this is speeding 8) Feet between bases 9) Fifteen times six 10) Four score and ten 11) Fourscore and ten 12) Good test grade 13) Heading for a centenary 1) Xc 
• (n.) A symbol representing ninety units, as 90 or xc. • (n.) The sum of nine times ten; the number greater by a unit than eighty-nine; ninety units or objects. • (a.) Nine times ten; eighty-nine and one more; as, ninety men. • (n.) The sum of nine times ten; the number greater by a unit than eighty-nine; ninety units or object...
Nine'ty adjective [ See Nine , and confer Forty .] Nine times ten; eighty-nine and one more; as, ninety men. Nine'ty noun ; plural Nineties 1. The sum of nine times ten; the number greater by a unit than eighty-nine; ninety units or objects. 2. A symbol representing ninety units, as 90 or xc. 
[adj] - being ten more than eighty 2. [n] - the cardinal number that is the product of ten and nine
90 adjective being ten more than eighty