Other forms: regimens
A regimen is a fixed routine of care followed daily. A skincare regimen, a strict regimen, follow the regimen.
It is the medical and cosmetic word for a prescribed course — a treatment regimen, an exercise regimen — and the fixedness is the point, since these things work by repetition. Note the near-neighbours: a regime is a system of government or, loosely, the same as a regimen, and a regiment is a military unit. All three come from the same Latin word about ruling.
1nounregimenA fixed routine of care followed daily.
“Her daily regimen includes a morning run and an hour of piano practice.”
regimen is a prescribed routine.
Latin regimen means guidance or rule, from regere, to rule. Regime, regiment, regular and rex come from the same ruling.
Proto-Indo-European
*h₃reǵ-
Latin
regimen — guidance, direction, government, rule
Middle French
regimen
Middle English
regimen
English, today
regimen
From Middle English regimen, from Middle French regimen and its etymon, Latin regimen (“guidance, direction, government, rule”). a doublet of regime.
Etymology from Wiktionary, CC BY-SA