Zygote, fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm). In the embryonic development of humans and other animals, the zygote stage is brief and is followed by cleavage, when the single cell becomes subdivided into smaller cells. zoom_in.
[edit on Wikidata] A melanocytic nevus (also known as nevocytic nevus) is a type of lesion that contains nevus cells (a type of melanocyte). Some sources equate the term mole with melanocytic nevus. Other sources reserve the term mole for other purposes. The majority of moles appear during the first two decades of a person's life, with about one in every 100 babies being born with moles.
Blue nevus. Blue nevus (also known as blue neuronevus, dermal melanocytoma, and nevus bleu) is a type of melanocytic nevus. The blue colour is caused by the pigment being deeper in the skin than in ordinary nevi. In principle they are harmless but they can sometimes be mimicked by malignant lesions, i.e. some melanomas can look like a blue nevus.