Hens and chickens in German
An owl should be able to distinguish a hen from a chicken in German, too!
Huhn - Hühner is the generic term for the type of animal.
"Huhn" is also used for the female animal, as is "Hahn" for the male
A "Henne" is a female that hatches / has chicks
"Küken" is chick
"Hähnchen" is a young male chicken meant for frying
"Gockel" is another word for "Hahn", also used to described a vain person.
I'm sure chicken farmers differentiate more, but these are the words lays use.
Admittedly this issue has always confused me as well.
Chicken = The general term for the species as a whole. This includes both male and female adults.
Chick = Just like “Chicken” this is a term for the species as a whole, both male and female. But this term is for young males and females that have not reached adulthood yet.
Hen = This term is for an adult female chicken.
Pullet = This is a young female chicken that has not reached adulthood yet. Basically pullets haven’t reached the age where they start laying eggs.
Rooster = An adult male chicken. These are the ones that crow, generally starting super early in the morning.
Cockerel = A young male chicken that has not reached adulthood yet.
In America this stands true. In Australia and New Zealand you'll find: https://en.oxforddictionaries.com/definition/chook