'archmarshal' originates from a combination of the prefix 'arch-' and the noun 'marshal'. 'arch-' comes from Greek 'arkhē' where 'arkh-' meant 'chief, principal', and 'marshal' comes from Old High German 'marhscalc' where 'marh' meant 'horse' and 'scalc' meant 'servant'.

'marshal' passed into Old French as 'mareschal' (from Old High German 'marhscalc'), then into Middle English as 'marshal' and developed into modern English 'marshal'. The compound 'arch-' + 'marshal' is a more recent English formation applying the Greek-derived intensifying prefix 'arch-' to create a superlative or chief-title form 'archmarshal'.

Initially, elements meant 'chief' (arch-) and literally 'horse-servant' (marshal), reflecting an officer in charge of horses; over time 'marshal' became a general term for a high-ranking military or ceremonial officer, and 'archmarshal' came to mean the highest-ranking marshal or chief marshal.