What does "nepotism" mean?

Nepotism: Undue attachment to relations; favoritism shown to members of one's family; bestowal of patronage in consideration of relationship, rather than of merit or of legal claim. From nepotism Alexander V. was safe; for he was without kindred or relatives. But there was another perhaps more fatal nepotism, which turned the tide of popularity against him -- the nepotism of his order. Milman.