What does acclimate mean?
To acclimate is to become accustomed to new surroundings — most literally to a different climate, but by natural extension to any unfamiliar environment or set of conditions. A traveler might acclimate to the humidity of the tropics, an athlete to the reduced oxygen of high altitude, or a new employee to the rhythms of a workplace. The verb is almost always intransitive, pairing with the preposition 'to' (as in 'acclimate to the cold'), and it carries no strong connotation: it suggests gradual, often physiological adjustment rather than dramatic change. American English strongly favors 'acclimate,' while British English generally uses the near-identical 'acclimatize'; both derive from the same root as 'climate' itself. The word is useful precisely because it spans registers — at home in a physiology textbook describing heat adaptation and equally natural in casual conversation about settling into a new home — making it a versatile term for the universal experience of adapting to change.
verbTo become accustomed to a new climate, environment, or set of conditions; to adjust physiologically or psychologically to changed surroundings.
- (intransitive) To become accustomed to a new climate or environment.
- (intransitive, by extension) To become habituated to any new situation, conditions, or circumstances.
"After a week in the highlands, the hikers had acclimated to the thin mountain air."
"It took several days for the runners to acclimate to the desert heat before the marathon."
"New employees usually need a few weeks to acclimate to the pace of the office."
The word 'acclimate' is essentially 'climate' wearing a prefix — English speakers literally borrowed the idea of adjusting to weather straight from the French.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of acclimate
Acclimate comes from French 'acclimater', formed by attaching the prefix 'a-' (from Latin 'ad-', meaning 'to') to 'climat', which itself traces back through Latin 'clima' to Greek 'klima', meaning 'slope' or 'region' — the ancient idea that climate varied with the inclination of the sun. The verb entered English usage in the early nineteenth century, alongside its longer variant 'acclimatize'. Its cognates include 'climate', 'climatic', and 'acclimatization', all sharing that same Greek root.
Related word forms
How acclimate is actually used
'Acclimate' is the standard form in American English, while British English typically prefers 'acclimatize'; both are fully accepted. The word is neutral in register and works equally well in scientific writing about altitude or temperature and in everyday talk about settling into a new job, city, or routine. It is normally intransitive, taking 'to' before the condition being adjusted to.
Easily confused with acclimate
Acclimatize is simply the British-preferred variant of the same verb; both mean to become accustomed to new conditions, with 'acclimate' favored in North America.