familiar

adj

1. Known to one, or generally known; commonplace.

   “There’s a familiar face; that tune sounds familiar.”

   “The story struck the depressingly familiar note with which true stories ring in the tried ears of experienced policemen. No one queried it. It was in the classic pattern of human weakness, mean and embarrassing and sad.”

   “Plastics are energy-rich substances, which is why many of them burn so readily. Any organism that could unlock and use that energy would do well in the Anthropocene. Terrestrial bacteria and fungi which can manage this trick are already familiar to experts in the field.”

2. Acquainted.

   “I'm quite familiar with this system; she's not familiar with manual gears.”

3. Intimate or friendly.

   “We are on familiar terms now; our neighbour is not familiar”

   “Don’t be familiar with me, boy!”

   “Be thou familiar; but by no meanes vulgar:[…]”

4. Of or pertaining to a family; familial.

   “1822, Lord Byron, Werner familiar feuds”

noun

1. An attendant spirit, often in animal or demon form.

   “The witch’s familiar was a black cat.”

   “The familiars of the magicians, on the other hand, were not in all cases evil, and often may have approximated the "guides" with whom present-day spiritualists are well acquainted.”

   “"What power hath gold?" Catweazle wondered as he picked up his familiar and put him in his special pocket.”

2. (obsolete)A member of one's family or household.
3. A member of a pope's or bishop's household.
4. (obsolete)A close friend.

   “[A] friend of mine, that finding a Receipt in Braſsivola, would needs take Hellebor in ſubſtance, & try it on his own perſon; but had not ſome of his familiars come to viſite him by chance, he had by his indiſcretion hazarded himſelfe; many ſuch I have obſerued.”

5. (historical)The officer of the Inquisition who arrested suspected people.