'Order' began as soldiers in formation — from Latin 'ordo' (a row). 'Ordinary' literally means 'in the row.'
The arrangement or disposition of people or things in relation to each other according to a particular sequence, pattern, or method; an authoritative command.
From Old French 'ordre,' from Latin 'ōrdō' (genitive 'ōrdinis,' a row, a rank, a series, a regular arrangement), of uncertain further etymology — possibly from PIE *h₂er- (to fit together, to join). The original Latin sense was a 'row' or 'rank' — soldiers standing in formation, threads arranged on a loom. The word's journey from 'a physical row' to 'abstract arrangement' to 'a command' to 'a
'Order,' 'ordain,' 'ordinary,' and 'extraordinary' all derive from Latin 'ōrdō' (a row). Something 'ordinary' follows the expected row — the regular sequence. Something 'extraordinary' is 'outside the row' — beyond the normal arrangement. To 'ordain' is to arrange someone into the priestly order. Even 'coordinate' means 'arranged together