As I have been taught by the Duolingo course, the word kioma is used when asking for the time:
Kioma horo estas?
I realise that it is made from the word kiom + -a (to make it an adjective?) but the other correlatives do not seem to have such forms (e.g. there is no tioa, kiea, etc.).
Is kioma an exception that is used only when asking for the current time or does it have a more broad meaning? Can you give any other examples of its use?