There is no synonym for awesome beginning with the letter x.
x-ray
A four letter word beginning with C and ending with X is crux.
What is a word that starts with X meaning nice or playful
xissing
xciting
NONE!
No because x isn't in the welsh alphabet
use a dictionary
xenoglossophobic which is the fear of foreign languages
Xenophobic
Xeno; strange, xero, dry