Xiv, xed, xii.
a four letter word beginning with X is xebec (a small historical three masted sailing ship with square sails.
A four letter word beginning with C and ending with X is crux.
There are none.
There is no synonym for awesome beginning with the letter x.
X-rayXenonXeroxSince the question asked for "three-letter" words beginning with "X", how about "xis"?
x-ray
Coxa
use a dictionary
Xenophobic
xis
pixieish
A three letter word that ends in the letter x could be the word Hex. A hex is a witches curse or spell.