nag

Etymology 1

From Middle English nagg, nage, nagge (“horse, small riding horse, pony”), cognate with Dutch negge, neg (“horse”), German Nickel (“small horse”). Perhaps related to English neigh.

noun

1. A small horse; a pony.
2. An old, useless horse.
   We used to lure the nags into the back of our truck with oats and sugar, then we'd drive back to town to this warehouse and inject the nags with small quantities of morphine I'd stolen. 2011, James Ellroy, Clandestine, page 245
3. (obsolete, derogatory) A paramour.

Etymology 2

Probably from a North Germanic source; compare Swedish nagga (“to gnaw, grumble”), Danish nage, Icelandic nagga (“to complain”).

verb

1. (transitive, intransitive) To repeatedly remind or complain to (someone) in an annoying way, often about insignificant or unnecessary matters.
   The room is never cleaned, so her mother nags and nags until she explodes with frustration and threatens to sell her to the lowest bidder. 2006, Jerry Day, How to Raise Kids You Want to Keep
   Anyone would think that I nagged at you, Amanda! (From Amanda! by Robin Klein)
2. To bother with persistent thoughts or memories.
   I guess it happens all the time in crime stories where the detective suddenly remembers a bit of conversation that nags him in some way, then for some inexplicable reason, it's just right there in front of you, like a sign pointing 'here! 2010, John David Wells, Diamonds of Affection and Other Stories, page 100
   Sometimes I write because there is a question that nags at me, sometimes because there is a question that nags at other people. 2010, John Goldingay, Key Questions about Christian Faith: Old Testament Answers
   You are sleeping on your side in the bed in your flat, heavily embroiled in a dream which sucks and nags at you and makes no sense; an old primary school teacher is there and a cat you have to take to a supermarket; you are in a canoe. 2013, Ra Page, L.E. Yates, Ann Winter, Parenthesis: A New Generation in Short Fiction
   The notion that he forgot something nagged him the rest of the day.
3. To bother or disturb persistently in any way.
   But at night, around the uncertain edge of dreams, and when the wind nags, there are few whom an odd sound will not thrill 1999, Tim Parks, Adultery and Other Diversions
   When a breeze comes up and nags the surface, it sparkles like a gemstone. 2013, Tina Egnoski, Perishables
   We are well accustomed as we look out upon Nature at close range to see great creatures harrassed by little creatures. The lot of each big one seems to be in the keeping of some little one, which never quits it, nags it, stings it, wears it out, drives it desperate, makes life somewhat a burden to it and death somewhat a relief. 2014, James Lane Allen, The Last Christmas Tree: An Idyl of Immortality, page 8
   a nagging pain in his left knee
   a nagging north wind

noun

1. Someone or something that nags.
   'That fellow is a nag.' 'Aye, the worst kind,' agreed Hamish, and then smiled, and at that smile, Miss Gunnery thawed even more. 2011, M.C. Beaton -, Death of a Nag
   When we see Wolfe struggling with many depictions of woman characters throughout the novel (the earlier ones being nags and white trash), we greatly admire the development of this living tribute to Aline Bernstein, a woman whom he ends up despising in his later life. 2014, Louise Hathaway, Nags, Sluts, and A Deep-Breasted Soulmate from the Shining City
   But, pchA has to produce more than awareness, always-on alerts/nags, or edu-tainment. 2015 -, Dwight McNeill, Using Person-Centered Health Analytics to Live Longer
2. A repeated complaint or reminder.
   And finally the biggest thank you of all to my partner Steven Winston for your love, enthusiasm, encouragement, support, humour, nags, and glasses of wine. 2011, Mike Bryant, Peter Mabbutt, Hypnotherapy For Dummies
   I turned it on Eileen and threw in a couple of my normal nags about her driving. 2015, Steve Brookstein, Getting Over the X, page 58
   A girl who expects her mother to nag her about her untidy bedroom will hear that message, even though the mother may want to talk about something quite different, so a loving invitiation to go shopping that started "When you've finished in your bedroom this morning. . ." might result in the child screaming, storming out and slamming the door because she expected this to be a nag about the state of the room and didn't let you finish with “ . . . shall we go to the shopping centre?”. 2016, Suzie Hayman, John Coleman, Parents and Digital Technology: How to Raise the Connected Generation
3. A persistent, bothersome thought or worry.
   During my lengthy aerobic strolls (which more or less served as a tool of meditation), that thought about “college” became a persistent nag. 2009, James Swift, How I Survived Three Years at a Two-Year Community College
   There are two ways to get rid of our nags. We can either use Ninja decision-making to turn them quickly into actions, stored in our second brain to be revisited when we have some time. Or we can simply just capture and collect the nag, knowing that our systems will ensure we return to it later. 2014, Graham Allcott, How to be a Productivity Ninja
   That feeling turned into a very persistent nag. 2016, Sarah Lowndes, The DIY Movement in Art, Music and Publishing

Etymology 3

noun

1. Misspelling of knack.