Carer

a state of mind in which one is troubled; worry, anxiety, or concern:
He was never free from care.
a cause or object of worry, anxiety, concern, etc.:
Their son has always been a great care to them.
serious attention; solicitude; heed; caution:
She devotes great care to her work.
protection; charge:
He is under the care of a doctor.
temporary keeping, as for the benefit of or until claimed by the owner:
He left his valuables in the care of friends. Address my mail in care of the American Embassy.
grief; suffering; sorrow.
to be concerned or solicitous; have thought or regard.
to be concerned or have a special preference (usually used in negative constructions):
I don’t care if I do.
to make provision or look out (usually followed by for):
Will you care for the children while I am away?
to have an inclination, liking, fondness, or affection (usually followed by for):
Would you care for dessert? I don’t care for him very much.
to feel concern about:
He doesn’t care what others say.
to wish; desire; like:
Would you care to dance?
couldn’t care less, could not care less; be completely unconcerned:
I couldn’t care less whether she goes to the party or not.
Also, could care less.
take care,

be alert; be careful:
Take care that you don’t fall on the ice!
take care of yourself; goodbye: used as an expression of parting.

take care of,

to watch over; be responsible for:
to take care of an invalid.
to act on; deal with; attend to:
to take care of paying a bill.

Contemporary Examples

“My carer is my boyfriend, and I need to be accompanied by him in most places,” she writes.
#YesAllWomen, but Not Really: How Feminism Leaves the Disabled Behind Elizabeth Heideman November 23, 2014

noun
(social welfare) a person who has accepted responsibility for looking after a vulnerable neighbour or relative Usual US and Canadian term caregiver See also caretaker (sense 3)
verb
(when transitive, may take a clause as object) to be troubled or concerned; be affected emotionally: he is dying, and she doesn’t care
(intransitive; foll by for or about) to have regard, affection, or consideration (for): he cares more for his hobby than his job
(intransitive) foll by for. to have a desire or taste (for): would you care for some tea?
(intransitive) foll by for. to provide physical needs, help, or comfort (for): the nurse cared for her patients
(transitive) to agree or like (to do something): would you care to sit down, please?
for all I care, I couldn’t care less, I am completely indifferent
noun
careful or serious attention: under her care the plant flourished, he does his work with care
protective or supervisory control: in the care of a doctor
(often pl) trouble; anxiety; worry
an object of or cause for concern: the baby’s illness was her only care
caution: handle with care
care of, at the address of: written on envelopes Usual abbreviation c/o
(social welfare) in care, into care, made the legal responsibility of a local authority by order of a court
noun acronym
Cooperative for American Relief Everywhere, Inc.; a federation of US charities, giving financial and technical assistance to many regions of the world
communicated authenticity, regard, empathy: the three qualities believed to be essential in the therapist practising client-centred therapy
n.

Old English caru, cearu “sorrow, anxiety, grief,” also “burdens of mind; serious mental attention,” from Proto-Germanic *karo (cf. Old Saxon kara “sorrow;” Old High German chara “wail, lament;” Gothic kara “sorrow, trouble, care;” German Karfreitag “Good Friday”), from PIE root *gar- “cry out, call, scream” (cf. Irish gairm “shout, cry, call;” see garrulous).

Different sense evolution in related Dutch karig “scanty, frugal,” German karg “stingy, scanty.” The sense development in English is from “cry” to “lamentation” to “grief.” Meaning “charge, oversight, protection” is attested c.1400, the sense in care of in addressing. To take care of “take in hand, do” is from 1580s.
v.

Old English carian, cearian “be anxious, grieve; to feel concern or interest,” from Proto-Germanic *karojanan (cf. Old High German charon “to lament,” Old Saxon karon “to care, to sorrow”), from the same source as care (n.). OED emphasizes that it is in “no way related to L. cura.” Related: Cared; caring.

To not care as a negative dismissal is attested from mid-13c. Phrase couldn’t care less is from 1946; could care less in the same sense (with an understood negative) is from 1966. Care also figures in many “similies of indifference” in the form don’t care a _____, with the blank filled by fig, pin, button, cent, straw, rush, point, farthing, snap, etc., etc.

Positive senses, e.g. “have an inclination” (1550s); “have fondness for” (1520s) seem to have developed later as mirrors to the earlier negative ones.
Cooperative for American Relief Everywhere
Cooperative for American Relief to Europe
Ryan White Comprehensive AIDS Resources Emergency Act
In addition to the idiom beginning with
care