A — 1: σίδηρος
(Strong's #4604 — Noun Masculine — sideros — sid'-ay-ros )

"iron," occurs in Revelation 18:12 .

B — 1: σιδήρεος
(Strong's #4603 — Adjective — sidereos — sid-ay'-reh-os )

"of iron," occurs in Acts 12:10 , of an iron gate; "of iron," Revelation 2:27; 9:9; 12:5; 19:15 .