noun

• (zoology) A crustacean larva that has three pairs of locomotive organs (corresponding to antennules, antennae, and mandibles), a median eye, and little or no segmentation of the body.
  "The oval body, with the abdomen not yet differentiated, and bearing no limbs; the (usually) three pairs of limbs, representing the first and second antennæ and mandibles of the adult, together with the single eye, are the distinguishing characteristics of the nauplius stage."

name

• (Greek mythology) A son of the god Poseidon by Amymone, daughter of Danaus, and founder of the city of Nauplia.
• (Greek mythology) A descendant of the founder of Nauplia who ruled the city (alternatively, Euboea), was one of the Argonauts, and was father to Palamedes, who fought in the Trojan War.
  "But according to Lycophron, the last of the Greek poets, Penelope committed adultery with one of the suitors at the persuasion of the aged Nauplius, who avenged the death of his son Palamedes by enticing almost all the wives of the Greeks into prostitution."