(archaic) simple past tense and past participle of can

Something that could happen, or could be the case, under different circumstances; a potentiality.

simple past tense of can / Used as a past subjunctive (contrary to fact). / Used to politely ask for permission to do something. / Used to politely ask for someone else to do something.

Eye dialect spelling of could have or could've. / Misconstruction of could have or could've.

plural of could

To need something that would be beneficial.

(double modal / stacked modal, used in some dialects, chiefly Southern US) might be able to (used to soften "could" or make it even more conditional)

simple past tense of could do with / simple past tense of can do with

(US, sometimes proscribed) To not care at all; to have no concern or interest; to be apathetic.

(idiomatic, anapodoton) Used to characterize a look of strong hostility