What does acclimatized mean?
Acclimatized is the past tense and past participle of the verb acclimatize, meaning to have become accustomed to a new climate, environment, or set of conditions. The word is most often used literally for physiological adjustment — hikers becoming acclimatized to high altitude, or animals acclimatized to a new habitat — but it is also widely used figuratively for anyone who has grown used to unfamiliar circumstances, from a new job to a foreign city. It is standard in British English, where the verb is spelled acclimatise in its base form, while American English typically prefers acclimated. The term carries a neutral, practical tone and appears frequently in scientific, medical, and travel writing. Its root lies in the word climate, from the Greek klima, meaning inclination or zone of the earth, reflecting the word's original focus on weather and environment.
verb (past tense and past participle of acclimatize)Having become accustomed to a new climate, environment, or set of conditions. It describes the state reached after a person, animal, or thing has adjusted physiologically or practically to unfamiliar surroundings.
- Having become physiologically accustomed to a new climate or environment, such as altitude or temperature.
- Having adjusted generally to new or unfamiliar conditions or circumstances (figurative use).
"After a week in the highlands, the climbers were fully acclimatized to the thin air."
"The athletes spent two weeks in Denver before the race so they would be acclimatized to the altitude."
"New employees usually feel acclimatized to the office routine within a month."
Your body literally grows new red blood cells to become acclimatized at high altitude — it's adaptation you can measure in a blood test.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of acclimatized
Acclimatized derives from the verb acclimatize, which was formed in the late 18th or early 19th century from the French acclimater, itself built from the prefix a- (from Latin ad-, meaning to) plus climat, the French form of climate. The word climate traces back through Latin clima to the Greek klima, meaning slope or inclination, originally referring to the angle of the sun and hence to zones of the earth. English also developed the shorter variant acclimate in American usage, and the noun acclimatization denotes the process itself.
Related word forms
How acclimatized is actually used
The spelling acclimatized is standard in British English; American English more often uses acclimated, while acclimatize remains common in both varieties. The word is neutral in register and appears in both scientific writing (physiology, mountaineering) and everyday speech. The figurative sense — adjusting to any new situation, not just climate — is fully accepted.
Easily confused with acclimatized
Acclimated is the American variant of the same verb, while acclimatized is the form more standard in British English; both mean the same thing.
Acclimatized refers to adjusting to physical or environmental conditions, whereas acculturated refers to adapting to a different culture or social norms.