What is meant by term 'RC' & 'FC' in case of a bicycle frame
I came across a engineering drawing for one of the bicycle alloy frames (MTB).
There was mention RC distance on the drawing from BBS centre till the dropout dead centre towards rear and FC distance from BBS centre till imaginary fork dropout dead centre.
Can anyone tell me what is the full form of "RC" and "FC".
I know that totaling both the dimensions gives us wheelbase.