During which weeks of nouns is the babe call fetus?

And during which weeks of development is the kid considered an embryo?During which weeks of nouns is the babe call fetus?
An embryo is from implantation in the uterus until the 8th week. The fetal stage begin at the end of the 8th until birth. After birth, for the first month, the child is called a neonate.
From week 1 to 39.
My widget dictionary say after 8 weeks for a fetus, and in the first 8 weeks after conception it is an embryo. So, first 8 wks it is an embryo, after that a fetus.
After fertilisation the embryo develops and is prearranged as an embryo until after the 8th week of conception. After the eighth week the embyro is known as a foetus. The foetus stage continues until birth. So, the toddler is known as a foetus from week 8 through to week 40 (if carried full term) or time of birth. Hope this helps.
my psychology books say that it's an embryo from the beginning of the 3rd week until the call a halt of the 8th week. It also says that it's call a fetus from the beginning of the 9th week until birth.