Strong's G2757 — κενοφωνία (noun)
kenophonia (ken-of-o-nee'-ah) n.
1. empty sounding, i.e. fruitless discussion
[from a presumed compound of G2756 and G5456]
KJV: vain 
Root(s): G2756, G5456 
Hebrew root: φωνή
Occurrences: 2