ssh on lan by hostname instead of dynamic ip

[BartlebyScrivener <bscrivener42@gmail.com>]

Hello,

I use unison and rsync on my home LAN. Everything works fine as long
as I use ip addresses, for example,

ssh rick@192.168.0.5

But my router (on home LAN) assigns dynamic ip addresses. So my
scripts don't work if the router happens to assign a different address
that day to one of my machines.

Is there a way to use ssh and rsync using hostname instead of ip
address. It seems to me I've had this working once or twice, but then
it stops.

Thanks for any help.

rick