I use the word "chicken" to primarily refer to a hen, or female chicken, although chickens in a general sense could include the males or "roosters". Chicken also refers to the food. A "chick" is what comes out of the egg until it gets too big to look cute. One thing I was told to be wary of with chicks is not to hug them to your cheek or give them a kiss because they do peck and could cause damage, but I was never tempted to cuddle with them.
Since I took care of chickens on our family farm (both hens and some roosters), cleaning the house, adding bedding, picking up eggs, they were never viewed as pets, but I can see how they might be. The handful of chickens I obtained later that the bad dog got his jaws into I picked up on my own. I was told by a neighbor that the hen ate those chicks because she needed calcium. I got them some minerals to supplement their food, just in case, but I don't know if that guy knew what he was talking about.