unaccustomed to

unaccustomed to (someone or something)

Not habituated or used to someone or something. The spoilt boy was unaccustomed to hard work, and he complained endlessly of having to soil his hands and strain his muscles. I've been working from home for so long that I feel like I'm growing unaccustomed to other people.
See also: unaccustomed
Farlex Dictionary of Idioms.

unaccustomed to someone or something

not used to someone or something. The poor family was unaccustomed to going to fancy restaurants. Bill was unaccustomed to mailing his own letters.
See also: unaccustomed
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • unaccustomed
  • unaccustomed to (someone or something)
  • get used to (someone or something)
  • habituate
  • habituate (someone) to (something)
  • habituate to
  • it takes (some) getting used to
  • it takes getting used to
  • set in one's ways, be
  • be set in your ways
References in classic literature
From there on the homeward journey was slow, as these proud fighting men were unaccustomed to the duties of porters.
From this it came to pass that Italy fell partly into the hands of the Church and of republics, and, the Church consisting of priests and the republic of citizens unaccustomed to arms, both commenced to enlist foreigners.
Meriem, entirely unaccustomed to the companionship of such as Baynes, was fascinated by him.
But it was not thus in the present case with the Pequod's sharks; though, to be sure, any man unaccustomed to such sights, to have looked over her side that night, would have almost thought the whole round sea was one huge cheese, and those sharks the maggots in it.
But the Square is so unaccustomed to the use of the moral terminology of Spaceland that I should be doing him an injustice if I were literally to transcribe his defence against this charge.
But I did get a jingle twice each day; and the amount of alcohol I consumed every day, if loosed in the system of one unaccustomed to drink, would have put such a one on his back and out.
This suggests a broader appeal to consumers who are unaccustomed to buying luxury cars, the analyst says.
Some, like Carl Reiner and Mel Brooks and Henry Kissinger, are well-known, but many others are not, and, being unaccustomed to appearing on camera, deliver emotional and deeply moving monologues as they recall the events that shaped their lives.
We are also unaccustomed to losing at home, so this is a bit of a shock to the senses.
The village's residents pass the incident off as excessive nervousness on the part of city-folk unaccustomed to rural life.
Many firms are unaccustomed to this vital aspect of business.
But he has bravely battled to the top of his sport and is relishing a rare trip to the UK to sample a way of life and style of golf he's unaccustomed to.
Abu Dhabi, the UAE capital, is regarded as more conservative than its cosmopolitan neighbour, Dubai, which is more frequented by Western travellers unaccustomed to the Islamic call to prayer.
I, too, have taken root, like a sore vessel unaccustomed to the sea.
Few deaf people are unable to voice but prefer not to put themselves at risk of attracting embarrassing attention from those unaccustomed to deaf speech.