What would you call this?

[chandylier]

A sports top (trousers to match)
It's just got a small zip at the top, so not a track suit top.
Ds's mate looked at me like I had 2 heads. I called it a sweater, which I know it's not, but I couldn't think of a word for it.
We're not local, I have no idea what they would call it

top/jumper

Tracksuit/trackie top?
This thread reminded me of when my DD was a baby,and my late DM kept calling DD's woollen tights,jeans! I kept correcting her and she just said 'Well,I don't know what items of clothing are called nowadays'. They're tights,mum!

We call them half zips too

It would be a half zip in my house too - although the zip usually goes down a bit further than just the neck. My daughter wears them for PE and for running around in. Sweater to me is a "old fashioned" word like slacks. I usually use the word top for anything with sleeves.

Leesure Suit obvs

Top

...& I’d look at you like ‘say what?’ if you called it a sweater too.

🤣