[SaveFerris]

The word for “mark” in Revelation 13:16-18 is “charagma”

Greek word “charagma”:

https://biblehub.com/greek/5480.htm

Strong’s Concordance

charagma: a stamp, impress
Original Word: χάραγμα, ατος, τό
Part of Speech: Noun, Neuter
Transliteration: charagma
Phonetic Spelling: (khar’-ag-mah)
Definition: a stamp, impress
Usage: sculpture; engraving, a stamp, sign.

HELPS Word-studies

5480 xáragma – properly, an engraving (etching); (figuratively) a mark providing undeniable identification, like a symbol giving irrefutable connection between parties.

5480 /xáragma (”brand-mark”) was originally any impress on a coin or a seal, used by an engraver on a die (stamp, branding iron). 5480 (xáragma) later became “the identification-marker” (like with an owner’s unique “brand-mark”).

[SaveFerris]

I’d have to look at the other verses but here is Revelation 13:16

Revelation 13:16 Greek - English Bible

I’m unable to preserve the formatting (I tried!)

https://biblehub.com/interlinear/revelation/13-16.htm