Lexical Definition

‎ἀμίαντος‎ amíantos (am-ee'-an-tos) pure ^G:A
from ‎Α‎ (as a negative particle) and a derivative of ‎μιαίνω‎

undefiled.

• unsoiled, i.e. (figuratively) pure

Abbott-Smith

** ἀ-μίαντος, -ον (< μιαίνω), [in LXX: Wi 3:13 4:2 8:20, II Mac 14:36 15:34*;]
undefiled, free from contamination (in π., of αἰθήρ; MM, VGT, s.v.): He 7:26 13:4, I Pe 1:4, Ja 1:27.†
SYN.: ἄμωμος, ἄσπιλος (Cremer, 784).

Abbott-Smith References

Liddell-Scott-Jones

ἀμίαντος, ον,

undefiled, pure, ὕδωρ[Refs 6th c.BC+] calls the sea ἡ ἀμίαντο; ἀ. τοῦ ἀνοσίου πέρι free from stain of ungodliness, [NT+5th c.BC+]

__2 not to be defiled, [Refs 1st c.BC+]
__II ὁ ἀ. λίθος asbestos, [Refs 4th c.BC+]

_{LSJ Scripture Refs: Heb.13.4 ☩ 1Pet.1.4}