Noun
ようし
あの駅長の子は、どうやら養子らしいです。
I heard that station master's kid is actually an adopted child.
わたしの友人は九月に養子をむかえいれることにした。
My friend decided to adopt a child in September.
養子の態度が悪いから、叱ってやったんだ。
I scolded my adopted child because he has such a bad attitude.
A foster child you bring into your family is your adopted child.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.