Lexical Definition

‎σάκκος‎ sákkos (sak'-kos) sackcloth ^G:N-M
of Hebrew origin (‎שַׂק‎)

sackcloth.

• "sack"-cloth, i.e. mohair (the material or garments made of it, worn as a sign of grief)

Abbott-Smith

σάκκος also written σάκος, -ου, ὁ (cf. Heb. שַׂק, which it renders in LXX),
1. a coarse cloth, sackcloth, usually made of hair: Re 6:12.
2. Anything made of sackcloth;
(a) a sack (Ge 42:25, al.);
(b) a garment of sackcloth, expressive of mourning or penitence: Mt 11:21, Lk 10:13, Re 11:3.†

Abbott-Smith References

Liddell-Scott-Jones

σάκκος

or σάκος, ὁ, see entry near the end:— coarse cloth of hair, especially of goats' hair, σάκκος τρίχινος [LXX+NT]

__II anything made of this cloth:
__II.1 sack, bag, [Refs 5th c.BC+]
__II.2 sieve, strainer, especially for wine, [Refs 6th c.BC+]
__II.3 coarse garment, sackcloth, worn as mourning by the Jews, [LXX+NT+1st c.AD+]
__III coarse beard, like rough hair-cloth, σάκον πρὸς ταῖν γνάθοιν ἔχειν [Refs 5th c.BC+] —The form σάκος is said to be Attic dialect, [Refs 2nd c.AD+] R., etc.; while σάκκος is called Doric dialect by [σάκκος in “Ach.” 745 (from Megarian), and in 6th c.BC: Hipponax Iambographus [same place]; codices of 5th c.BC: Herodotus Historicus give σάκκος">Refs 6th c.BC+]. Inscrr. have σάκος [σάκκος [prev. work] 198">Refs]: Papyri have σάκος [Refs 3rd c.BC+], but oftener σάκκος [Refs 3rd c.BC+], etc. (Prob. the word, like the thing, was borrowed from Phoenicia, cf. Hebrew saq.)

_{LSJ Scripture Refs: Rev.6.12 ☩ LXX.Isa.50.3 ☩ LXX.Gen.37.34 ☩ Luke.10.13}