Onomastics is incorrectly written, and should be written as "onomastics" being its meaning:
Word of Greek origin, onoma onomatos: name and suffix - ikos - ike - ikon: relative a: relation to the name. It is the feast of the Christian Saint in whose honor the named person. In the Christian tradition put to children the name of the Saint or Holy of Saints, corresponding to the day of the birth, which used to match the anomastica birthday. But it is not always the case. Latin America uses the masculine.
