Sunday

UK: /ˈsʌndeɪ/, /ˈsʌndɪ/ US: /ˈsʌndeɪ, -di/ ,(sun′dā, -dē)

WordReference Random House Learner's Dictionary of American English © 2025

Sun•day /ˈsʌndeɪ, -di/   n. 

1. the first day of the week, observed as the Sabbath by most Christian denominations:
   [proper noun] On Sunday they would go to church.
   [countable] We saw him two Sundays ago.

adj. [before a noun]

2. of or relating to Sunday.
3. used, done, or taking place only on or as if on Sundays:
   a Sunday matinée.

WordReference Random House Unabridged Dictionary of American English © 2025

Sun•day  (sun′dā, -dē), n. 

1. Biographical the first day of the week, observed as the Sabbath by most Christian sects.
2. a month of Sundays, an indeterminately great length of time:
   She hadn't taken a vacation in a month of Sundays.

adj. 

3. of, pertaining to, or characteristic of Sunday.
4. used, done, taking place, or being as indicated only on or as if on Sundays:
   a Sunday matinée.

• bef. 900; Middle English sun(nen)day, Old English sunnandæg, translation of Latin diēs sōlis, itself translation of Greek hēméra hēlíou day of the sun; cognate with German Sonntag

Sun′day•like′, adj. 

Sun•day  (sun′dā, -dē), n. 

William Ashley  (ash′lē), ("Billy Sunday''), 1862–1935, U.S. evangelist.
1. a female given name.

Collins Concise English Dictionary © HarperCollins Publishers::

Sunday / ˈsʌndɪ -deɪ/ noun

1. the day after Saturday and before Monday: the Christian day of worship

Etymology: Old English sunnandæg, translation of Latin diēs sōlis day of the sun, translation of Greek hēmera hēliou; related to Old Norse sunnu dagr, German Sonntag