If they did not get the wrong dictionary and it turns out that it is Galician/xelo ( ice), then it must be a searched form for Chelo (hypocoristic of "Marcellus" ).
It means Chelo, Celo, apocope of Marcelo. Affectionate way to call the one whose name Marcelo has.
XELO In Chile, colloquial form of writing cello, apocope by Marcelo.