Where does “officiarius” come from?

officiarius (Latin) comes from French officier, from German Offizier, from Old French officer, from Medieval Latin officiarius, from Latin officium, from Latin opificium, from Latin opifex, from Latin Ops — to throw, reach, pierce; to hit by throwing.

Ancestry of “officiarius”, step by step

Step	Language	Word	Meaning
1	French	officier	to officiate; officer
2	German	Offizier	officer, commissioned officer; any chess piece...
3	Old French	officer	officer
4	Medieval Latin	officiarius	officer
5	Latin	officium	duty, service; office; obligation, an obligatory...
6	Latin	opificium	work
7	Latin	opifex	Someone who does work ; worker, maker, framer,...
8	Latin	Ops	earth goddess, fertility deity
9	Latin	oscen	any bird by whose song cries augurs divined...
10	Latin	opscen	—
11	Latin	ob-	towards; against
12	Latin	obolus	obolus
13	Ancient Greek	ὀβολός	obol, obolus, used at Athens as both a weight and...
14	Ancient Greek	ὀβελός	a spit, rod; a horizontal line
15	Ancient Greek	βέλος	missile, arrow, dart; weapon; something quickly...
16	Proto-Indo-European	gʷélHos	—
17	Proto-Indo-European	gʷelH-	to throw, reach, pierce; to hit by throwing

Every word from Proto-Indo-European gʷelH- →