Short for Eleanor in English speaking countries, usually.
One of my nicknames used to be Nell. I like it.
I’ve seen both Nellie and Nancy used to refer to gay (or at least effeminate) men in old pulp fiction detective novels…enough that it is what I thought this thread would be about.
I have an Irish aunt “named” Nellie who’s over 90, and I’m over 50.
I got a phone call a few weeks ago. Her daughter called me, intriduced herself as my cousin (I have scads of them) and then said she was putting her mother “Eileen” on the phone.
I had no idea who she was, because in my whole like I’ve never heard her been referred to as anything but Nellie. But her real name is Eileen. I was so shocked I called my own sisters and asked if they had ever heard this. Neither of them had.
So, maybe Nellie is a familiar version of Eileen, or maybe my aunt just has a strange nickname.
It has a different connotation if you’re a fan of Arrested Development.
Maybe its short for Anna Lee sometimes, too.
Looking at my family tree I have one aunt who was actually christened “Nellie” (in 1912), and another one, born in 1894, who’s real name was Ellen but was called “Nell” by everyone.
My daughter Janel and my wife’s cousin Danelle are both called “Nellie” by our family.
Grim
I’ve heard it for Penelope.
I have never heard that. That’s my wife’s name, and she is always called Penny.
Penelope, my uncle’s cat, was nicknamed Nellie. Sorry, I don’t actually know any human Penelopes so that’s the best I can do. 
My daughter is an Eleanor called Nell. She is named after my grandmother who was a Helen. Helen, Ellen, and Eleanor are all closely derived names. Didn’t like Helen, liked Eleanor, liked Nell. Sometimes its short for something (in England and America, most commonly Eleanor), sometimes it stands alone.
Eleanor Roosevelt was a Nell as a child. Paul Newman’s daughter Nell is an Elinor. Nelle Harper Lee is a Nelle.
Trying to track one of my G.G.Grandmothers through the archives I found out that she first called herself Helen, but then changed this to Ellen later in life. This is as bad as another ancestor who started out as a Catherine and then changed this to Kate.
Names were pretty changeable (and to some extent still are - but we leave a better paper trail) before a lot of recordkeeping. My grandmother Helen was actually named Anna - the priest named her at baptism a name no one in the family wanted and no one in the family ever called her. Apparently, this wasn’t that uncommon.
My uncle (by marriage) had lived his life thinking his name was Gerald Patrick - until he needed to get a passport as an adult and had to go back to a birth certificate he’d never needed to use. His name was legally Patrick Michael.
And we aren’t being original when we just make up names out of whole cloth. That’s been going on forever. There are periods of time where there are a very few common names used over and over - there are also periods where people named children - particularly girls - strange things (Puritan names for women are amazing).
My little sister, Danielle, couldn’t say her name when she was little. She said “Nyell”, which became Nell, which became Nellie.
I have one in my tree - Temperance Knowle, born in 1693.
My sister in law’s nickname was Nanny, but HER given name was Gerry (pronounced “Gary”). Go figure.
And where is the nickname “Tutti” derived from? There was a very minor character in the movie “Goodfellas” named Tutti and even after asking Italian friends what this guy’s REAL name could have been, I still don’t know.
How about being named “The-Lord-Is-Near.” Or Flie-Fornication?
http://rjg42.tripod.com/puritan_names.htm
Another site on the quick search mentioned “Lamentation.” Made me want to have another daughter so I could name her Lamentation.
You’ll never make fun of an ordinary “McKynzzy” again…(ok, you will, but you’ll realize we aren’t the first culture for unusual names)
Me, too.
That blue me away.
Ellen, Eileen, Eleanor, and the like are all basically forms of Helen. Saying that “Nellie” is a diminutive for any of them is basically saying that it’s a diminutive of Helen.