'...a pale horse...'
5514 Chloe; feminine of apparently a primitive word; "green"; Chloe, a Christian female:--Chloe.
"The greenness is a sign of death. Death causes the face to turn green, as it says in the Talmud, referring to the angel of death: '...they throw in the mouth of the dying the drop which caused his death, and his skin and face become green' ('Avodah Zarah 26b)."
(Commentary to the New Testament, Yechiel Lichtenstein as quoted in Jewish New Testament Commentary by David Stern)
See also Leprosy.