I'm used to the ending " WCH" denoting a command. Are we being commanded to "HEDD"? In which case, what is "HEDD"? Just asking.
In the GPC dictionary, this seems to be from hedd (which also means "peace" + -wch(1) which is a noun ending, rather than with -wch(2) which is the command form verb ending or with -wch(3) which is the ending for some conjugated prepositions.
Thank you, mizinamo, though it does seem like demonstrating the difference between left and right using billiard balls as models. 3 different 'wch' s. Does it boil down to a matter of context which one applies?
Well, or a matter of history.
I don't see etymology information for any of those three suffixes but I imagine that it's just coincidence that they look the same in modern Welsh. (Well, 2 + 3 might be related as they're all related to chi, but 1 is probably separate.)
A bit like how "sticky" in English means something that sticks (is like glue), not something that is like a stick (a piece of wood) -- the two words "stick" happen to look the same. On the other hand, "rocky" is something that is like a rock, not something that rocks (back and forth).