General "baby":
* نوزاد (Nozād): This is the most common and general term for a baby. It can be used for both newborns and infants up to a certain age.
* بچه (Bacheh): This word literally means "child," but it's often used for babies or young children.
* کوچولو (Koocholu): This means "little one" and is a more affectionate term for baby.
Infant (specifically):
* شیرخوار (Shirkhavar): This specifically refers to an infant who is still breastfeeding.
* نوزاد شیرخوار (Nozād Shirkhavar): This means "breastfeeding infant".
Other related words:
* نوزاد تازه متولد شده (Nozād Tâze Motavallod Shodeh): This means "newborn baby."
* نوزاد دوقلو (Nozād Dogholu): This means "twin baby."
The best choice depends on the specific context and how you want to express the concept of "baby" or "infant" in Farsi.