the root rAdh has a lot of meanings from which rAdhA or rAdhikA has formed. some of the meanings are,
1). one who pleases
2). one who satisfies
3). one who accomplishes.
and so on.
type as I will instruct you as I cannot post a URL link
double-u double-u double-u dot spokensanskrit dot de and dont leave any spaces between them.
See if this can help.