Usage: 3 forms in 14 verses
Form Translated As     In Verse(s)
ιστίων shrouds LXX.Exod.27.14LXX.Exod.27.15
ιστίοισ shrouds LXX.Exod.38.18
ιστία shrouds LXX.Exod.27.9LXX.Exod.27.11LXX.Exod.27.12LXX.Exod.27.13LXX.Exod.35.17LXX.Exod.38.9LXX.Exod.38.13LXX.Exod.39.40LXX.Num.3.26LXX.Num.4.26LXX.Isa.33.23

Liddell-Scott-Jones

ἱστίον (histion) a shroud G:N-N

ἱστίον, τό

(diminutive of ἱστός in form only), web, cloth, sheet: hence in plural, hangings, [LXX]; as a measure, piece, [Refs 2nd c.BC+]; but,

__II from [Refs 8th c.BC+] downwards, sail, mostly in plural ἱστία, ἕλκον δ᾽ ἱστία λευκὰ.. βοεῦσιν they hauled them up with ox-hide ropes, [Refs 8th c.BC+]; τέταθ᾽ ἱστία the sails were spread,[Refs 5th c.BC+]; ἱστία στέλλεσθαι, μηρύεσθαι, καθελεῖν, to lower or furl sail (see entry): λύειν [Refs 8th c.BC+]. under full sail, with all one's might, [Refs 2nd c.AD+]: rarely in singular, ἐν δ᾽ ἄνεμος πρῆσεν μέσον ἱστίον [Refs 8th c.BC+]

LSJ Scripture Refs: LXX.Exod.27.9