fetus in fetu

== English == === Alternative forms === foetus in foetu === Etymology === From Latin fētus in fētū. === Noun === fetus in fetu (plural fetuses in fetu) (medicine, obstetrics) A fetus growing inside the body of another fetus, either from an unsuccessful twin pregnancy, or as a tumorlike growth. ==== Coordinate terms ==== chimeric conjoined heteropagus teratoma vanishing twin syndrome ==== Translations ====