I grew up in England and it was similar. Growing up Dinner was the hot meal using taken in the middle of the day either at school (dinner ladies), or at work (I imagined hot meals servers in factories or canteens). And tea (teatime!) was cold/lighter possibly taken with tea, essentially late afternoon tea, followed by supper later in the evening. Pretty sure it’s still like this in many places.

At some point dinner transitioned to lunch and teatime to dinner for us.