A grip using one hand with the thumb down and elbow out.
"The bartender gave me a gaston while pouring my drink, holding the glass firmly in his right hand with his arm extended outward."
To hold using such a grip
"The wrestler managed to gaston his opponent's arm before pinning him down."
A surname, from Old French of Norman French origin.
"During our family reunion, we discovered that several relatives share the surname Gaston, which traces back to its roots in Old and Norman French."