could

[kood, kuhd]

auxiliary verb

1. a simple past tense of can.

2. (used to express possibility).

   I wonder who that could be at the door. That couldn't be true.

3. (used to express conditional possibility or ability).

   You could do it if you tried.

4. (used in making polite requests).

   Could you open the door for me, please?

5. (used in asking for permission).

   Could I borrow your pen?

6. (used in offering suggestions or advice).

   You could write and ask for more information. You could at least have called me.

could

/ kʊd /

verb

1. used as an auxiliary to make the past tense of can 1

2. used as an auxiliary, esp in polite requests or in conditional sentences, to make the subjunctive mood of can 1

   could I see you tonight?

   she'd telephone if she could

3. used as an auxiliary to indicate suggestion of a course of action

   you could take the car tomorrow if it's raining

4. (often foll by well) used as an auxiliary to indicate a possibility

   he could well be a spy

Usage

See care.

Word History and Origins

Origin of could¹

First recorded in 1450–1500; alteration of late Middle English coude, coud, Old English cūthe; modern -l- from would ¹, should

Word History and Origins

Origin of could¹

Old English cūthe; influenced by _would , should; see _can ¹

Idioms and Phrases

see can (could) do with; see with half an eye, could. Also see under can; couldn't.

Example Sentences

This new design could illuminate the future of phone and computer screens as well as other lighting applications, all while minimizing sleep disruption caused by harsh artificial light.

Read more on Science Daily

“I didn’t think it could get better than last year,” Thomas said of his receiving corps, which now includes Dezeurn, a transfer from Bishop Alemany.

Read more on Los Angeles Times

And Huddleston isn’t confident that food banks and other community groups could even afford to pick up that slack.

Read more on Salon

Meanwhile, confusion continues over whether terminated employees will receive retroactive pay once the shutdown ends — an issue that could soon add another legal battle to the widening crisis.

Read more on Salon

Merseyside Police said Hayes entrusted his "graft phone" with key associates so they could continue supplying the illegal drugs while he took foreign holidays.

Read more on BBC

Related Words

• commit 
• manage 
• take care of