early 14c., althagh, compound of all + though, showing once-common emphatic use of all. "All though was originally more emphatic than though, but by 1400 it was practically only a variant of it, and all having thus lost its independent force, the phrase was written as one word" [OED].
1. Although he was only grumbling, his choice of words made Rodney angry.
2. Although they're expensive, they last forever and never go out of style.
3. Although people sometimes buy property sight unseen, it'sa remarkably bad idea.
4. Although this recipe looks long, it is actually very quick to prepare.
5. I was never really happy there, although the people were kindness itself.