Letters that make XXX
x are letters that make 'XXX'
LXXX, xxxi, xxxv, lxxx, cxxx are words created by adding a letter to 'XXX'
2 possible definitions for 'XXX'
Under this definition, xxx is a noun and has the following properties:
'XXX' can be a type of large integer.
Under this definition, xxx is a noun and has the following properties:
'XXX' can be a type of sex chromosome.
'XXX' can be a category of genetics, genetic science.