jacinth, a precious stone of the color of hyacinth.
Strong's:
ὑάκινθος
the "hyacinth" or "jacinth", i.e. some gem of a deep blue color, probably the zirkon Derivation: of uncertain derivation;
KJV Usage: jacinth.
TBESG:
ὑάκινθος
hyacinth
G:N-M
ὑακίνθος, -ου, ό [in LXX chiefly for תְּכֵלֶת ;] hyacinth; __(a) in cl., a flower, prob. the dark blue iris; __(b) in late writers, a precious stone of the same colour, perhaps the sapphire: Rev.21:20 (Phil., FlJ, al.).† (AS)
Thayer:
1) hyacinth, the name of a flower, also of a precious stone of the same colour, a dark blue verging on black
ὑάκινθος
huakinthos
hoo-ak'-in-thos
Of uncertain derivation; the “hyacinth” or “jacinth”, that is, some gem of a deep blue color, probably the zirkon