Horsemen - Vine's Expository Dictionary of New Testament Words
Horsemen
[ 1,,G2460, hippeus ]a horseman," is used in the plural in Acts 23:23, Acts 23:32.
[ 2,,G2461, hippikos ]
an adjective signifying "of a horse" or "of horsemen, equestrian," is used as a noun denoting "cavalry," in Revelation 9:16, "horsemen," numbering "twice ten thousand times ten thousand," RV.