IPA: /ædɒpˈtiː/
KK: /ædɑˈpti/
A person, especially a child, who has been taken into a family and given a new home and legal status as a member of that family.
The adoptee was welcomed into the family with open arms.
Adoptee is formed from "adopt" (from Latin "adoptare", meaning to choose for oneself) and the suffix "-ee" (meaning a person who is the recipient of an action). The word "adoptee" refers to a person who has been chosen and accepted into a family, typically through the legal process of adoption.
Think of someone who has been 'chosen' ('adopt') to become part of a family, and the '-ee' indicates that this person is the one receiving that choice.
No commonly confused words.