Strong's G3826 — παμπληθεί (adverb)
pamplethei (pam-play-thei') adv.
1. in full multitude, i.e. concertedly or simultaneously
[dative case (adverb) of a compound of G3956 and G4128]
KJV: all at once 
Root(s): G3956, G4128 
Hebrew root: πλήθος
Occurrences: 1