Fry. Or alevin.
Larva (the newly hatched form of an insect)
The word krill comes from a Norwegian word meaning freshly hatched fish.
The word FRY is used for small fish, especially young, recently hatched fish.Source: Thefreedictionary.com
Yes, the word chick is a noun, a singular, common, concrete noun; a word for a thing.
Hatched has one syllable.
The word 'snake' is a general term to describe a specific group of reptiles. A hatchling is the term given to a newly-hatched snake - up to about 3 months old.
The noun fish is an uncountable noun as a word for a type of creature or a food substance. The plural form for the noun phrase 'a newly discovered breed of fish' is 'newly discovered breeds of fish'.Although optional, the plural form for the noun fish can be used for two or more live fish, for example, 'There are three fishes in the pond.'
A newly invented word is a neologism.
One word: hatched.
The eggs hatched into baby chicks under the heat lamp.
seine
Also 'marlin' (other pronounciation though).