It is supposedly derogatory but the origin isn't really.
I spent a lot of my long vacations in the north of Nigeria growing up and asked questions about this word and this is what my relatives told me.

In northern Nigeria,it was common to see Hausas selling water on the streets,I saw that a lot in Jos.
They carried the containers tied to a wooden bar they hung on their necks

Igbos would yell out " Onye mmiri" which means " the one selling water" in order to attract the attention of the water seller
My family member had an eatery and we had an Onye Mmiri that came daily to fill up the container
Then the word Onye Mmiri i was told now became what they called their buyers and because of language,they called it Nyamiri which was the way it sounded to them.
The buyer called the seller Onye Mmiri,the seller called him nyamiri and with time Igbos and Easterners in general became known as Nyamiri.

This is a fascinating story,at least I was fascinated by it when I heard it.
It reminds me of how the word gay,an English word that is a synonym for happy has come to mean what it is not.
There are people named Gay,it sounds strange now when you hear it because of the metamorphosis the word has taken.
Interesting isn't it?

Who else has heard this story?

Heard the story too. It didnt begin from your generation though.

Odunnu: Heard the story too. It didnt begin from your generation though.

I hope I didn't give that impression
No it didn't start with my generation

i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

Please, do not start any unfounded crap. Ndigbo never begged anything from anybody in Nigeria. Which Igbo person was begging water in northern region before talk less during civil war?

Besides the British, most indigenous people of northern region looked upon Igbo as special creatures. BabyOsisi’s plank of the story is very truthful and the one that made rounds in my ears.

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

This is the version I know. I do not know where the OP got her own version from.

Dede1:

Please, do not start any unfounded crap. Ndigbo never begged anything from anybody in Nigeria. Which Igbo person was begging water in northern region before talk less during civil war?

err,oga i was just saying what i was told. you don't need to be angry. wetu o obi o?

LMAO

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

Correct version but it was before the civil war.

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

I know you are Igbo. You are 100% correct.

WTF is this. Hw will this change fuel prize?

Dede1:

Please, do not start any unfounded crap. Ndigbo never begged anything from anybody in Nigeria. Which Igbo person was begging water in northern region before talk less during civil war?

I thought you know much about your history? Go and read more sir. berem is 100% right.

bokohalal:

Correct version but it was before the civil war.

Oh before the civil war? wow! what must have prompted them to ask for water ? any historian in the house should please tell us.

bokohalal:

Correct version but it was before the civil war.

+1000

Well i don't know for sure about the origins of 'nyamiri', but i do know that Igbos call Hausa water carriers 'Aboki-me-rua'; right from my secondary school days in Igboland (Onitsha) this is how we refer to them.....how much more up in Ugwu-awusa, where we all know Igbos are quite adept in blending in and speaking the local language.

The version of the origin of 'nyamiri' i've heard is not as cute as the OPs own, and has its origins in the civil war.

bokohalal:

Correct version but it was before the civil war.

Before the war Igbos were the principals in virtually all the schools in the north
They were the teachers too
The were the railway and municipal workers
I had and still have some family in the north
They dominated every area of government because northerners did not go to school that much and still don't
My own husband was born and bred in the north and speaks Hausa like a native
This fact is recorded in virtually all civil war literature out there
Hausas were menial workers and did chores like fetch water and wood
Even today the average Igbo or southerner in the north is better off educationally and financially than his host
So what could have prompted Igbos to beg for water before the civil war ?
Under what circumstances?
Explain

Geomac:

I thought you know much about your history? Go and read more sir. berem is 100% right.

Where do we read that
Care to share

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

This is the version that i heard. Though i don't know if it's the real version.

Where are the Hausas on nairaland?

berem: i heard another version of the story. can't remember who told me but i was told during the war, igbos were seen begging for water from the hausas. I mean igbos who were still in the north during the war. the igbos would ask* nye m mmiri*. which means* give me water*.

ya! This is the best and most truthful rational behind the reason. At least it sounds and blends with the environmental circumstance of the name and issue that warranted it.

berem: Oh before the civil war? wow! what must have prompted them to ask for water ? any historian in the house should please tell us.

They were asking for water as visitors to ugwu-awusa NOT begging.......

In Igbo land those days, its known that you cant deny a visitor the courtesy of giving him/her water when they ask......Thus, Igbos believing that Ndi-awusas welcomes visitors like them, therefore asked for water from their host only to be rewarded with the derogatory name of NYAMIRI.

Afam4eva:
This is the version that i heard. Though i don't know if it's the real version.

maybe Google will help. 'off to Google. com '

babyosisi: Where are the Hausas on nairaland?

Proudly one!

chosen04:


They were asking for water as visitors to ugwu-awusa NOT begging.......

In Igbo land those days, its known that you cant deny a visitor the courtesy of giving him/her water when they ask......Thus, Igbos believing that Ndi-awusas welcomes visitors like them, therefore asked for water from their host only to be rewarded with the derogatory name of NYAMIRI.

What is derogatory in Nyamiri or Aboki for that matter

Odunnu:
Proudly one!

Odi egwu.

chosen04:


They were asking for water as visitors to ugwu-awusa NOT begging.......

In Igbo land those days, its known that you cant deny a visitor the courtesy of giving him/her water when they ask......Thus, Igbos believing that Ndi-awusas welcomes visitors like them, therefore asked for water from their host only to be rewarded with the derogatory name of NYAMIRI.

Sounds incredible
How many strangers have come begging you for water?
Remember there were public wind up mono pumps in the 40s and 50s built by colonial masters
Not that I was there but there are pictures of them

Odunnu:
What is derogatory in Nyamiri or Aboki for that matter

Or even ofenmanu and Okoro
They are not that bad IMHO

Afam4eva:
Odi egwu.

What?!

Odunnu:
What?!

Are you no longer from Bayelsa or Oyo again?

Afam4eva:
Are you no longer from Bayelsa or Oyo again?

Proudly Nigerian! Whichever one I choose, I can defend with supporting documents.

Nyamiri is a confirmed derogatory word from what i read in Google. whatever the case maybe, it doesn't stop igbos from being what they are. am proud to be a nwada igbo.