The 'yeah' means "oh yeah i thought about it" while the 'nah' relates to the answer

"yeah, i thought about it, but nah, dont think i will aye"

Very common expression in New Zealand
Hard to explain, but a very useful word, so not to hurt anyones feelings with a blunt 'nah'
"you going out tonight?"
"oh yea-nah, was gonna, but not anymore"
by Mauao November 7, 2007
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Yea nah means no but if someone goes nah yea that means yes but if someone goes yea nah yea that’s yes
Mate1: hey wanna beer
Mate2:yea nah yea cheers bruv
by Yeah nah yea true blue Aussie November 23, 2019
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a less harsh way of saying "no" to your mate
"oi yea nah mate I'm good"
by oi nah mate December 1, 2021
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