Merriam-Webster's Word of the Day for September 21, 2023 is: regimen \REJ-uh-mun\ noun

Regimen refers to a plan or set of rules about food, exercise, etc., designed to make someone become or stay healthy.

// Sherry’s personal trainer at the gym started her on a workout regimen of 30 minutes on the treadmill followed by 30 minutes of weight training.

[See the entry >](https://www.merriam-webster.com/dictionary/regimen)

Examples:

“For those with natural hair, taking on a protective hairstyle is more than an expectation, it’s a symbolic rite of passage. ... That said, tucking your hair into a protective style is not an excuse to completely disregard all hair-care practices. If anything, it's the exact opposite: Establishing an effective hair-care regimen is essential to maximizing and maintaining a protective style, so once it’s removed, both the scalp and hair are healthy and happy.” — Janelle Sessoms, Fashionista.com, 16 June 2023

Did you know?

Being but humble lexicographers, we cannot say whether an apple a day truly keeps the doctor away, but as far as regimens go, one could do a lot worse than snackin’ on a McIntosh. Regimen, which usually refers to a system of rules or guidelines—often for living a healthy life or taking a regular dose of exercise—comes ultimately from a Latin verb, regere, meaning “to direct.” Regere led in apple-pie order to the English word regimen, first by way of the Latin noun regimen, meaning “steering” or “control,” and then via the Medieval Latin regimen, referring to a set of rules. Other regere descendants fell further from the tree, including [correct](https://www.merriam-webster.com/dictionary/correct), [erect](https://www.merriam-webster.com/dictionary/erect), [region](https://www.merriam-webster.com/dictionary/region), [rule](https://www.merriam-webster.com/dictionary/rule), and [surge](https://www.merriam-webster.com/dictionary/surge). Be sure not to confuse regimen with another of its kin, [regiment](https://www.merriam-webster.com/dictionary/regiment), which refers to a military unit, as doing so could upset the apple cart.