Answer:

MASTER

AnswerCrossword Clue
MASTERMerchant ship captain
MASTERBecome expert in
MASTERLearn thoroughly
MASTERKind of key
MASTERTop chess player
MASTERReally learn
MASTERTony, to Jeannie
MASTERVirtuoso (and word that can follow the end of answers to starred clues)
MASTERKind of class or plan
MASTERZen teacher
MASTERGet the hang of
MASTERBecome an expert in
MASTERConquer
MASTERExpert
MASTERLearn all aspects of
MASTER.. of ceremonies
MASTERLearn how to do
MASTERGet down pat
MASTER.. of ceremonies (host)
MASTERGet down
MASTERDog owner
MASTEROriginal
MASTEROriginal document
MASTERPart of MC
MASTERPaterfamilias.
MASTERTeacher of disciples.
MASTER"The ... of Ballantrae."
MASTERTerm of address for a young man.
MASTERLord.
MASTERAn accomplished performer.
MASTERExpert.
MASTERPoet Henley, of his fate.
MASTERSkilled workman or artist.
MASTERTerm of address for a boy.
MASTERSkilled workman.
MASTERVanquish.
MASTER"... Skylark," John Bennett's book for boys.
MASTERJunior's title.
MASTERHead of the household.
MASTERPart of M. A.