baby
Baby birds are called chick / hatchlling / fledgling. There is no true scientific name for baby birds.
A group of hummingbirds is typically called a charm.
Baby hummingbirds are called chicks and are born without feathers. They grow rapidly and are ready to leave the nest within 3 weeks. Despite being so small, baby hummingbirds have a voracious appetite and need to be fed every 20 minutes by their mothers.
There is unlikely to be a specific name for a fear of hummingbirds but a fear of birds in general is called ornithophobia.
Charm
Hummingbirds are birds (Aves). A mammal is a warmblooded animal that nurses its young and ordinarily gives live birth (there are egg-laying mammals called monotremes).
Male hummingbirds are called cocks
Baby hummingbirds stay in a small cup-shaped nest made of plant material and spider silk. The nest is usually located on a tree branch or shrub for protection and camouflage. The mother hummingbird incubates and feeds the chicks until they are ready to fly.
The baby hummingbirds usually leave the home 2-3 weeks since born.
hummingbirds
The group is called Aves (birds) Trohilidae (family).
The mother hummingbird will drink nectar and eat bugs and then regurgitate the slurry substance the baby hummingbirds can digest. She will feed this mixture to the baby hummingbirds approximately every twenty (20) minutes. Baby hummingbirds cannot drink regular nectar as it does not contain enough protein to sustain them.