Haha, I do that too sometimes.
It's a thing in some Germanic languages. Instinct is to merge nouns into word, e.g. 'lawnchair', but that gives you a red squiggly line, but 'lawn chair' also looks wrong, so 'lawn-chair' is the middle ground.
First time I realised this was GCSE History lessons, looking at first world war posters like this one and going "huh, to-day with a hyphen…"
https://www.iwm.org.uk/collections/item/object/27774
First time I realised this was GCSE History lessons, looking at first world war posters like this one and going "huh, to-day with a hyphen…"
https://www.iwm.org.uk/collections/item/object/27774