Many animals have tails, which are the flexible appendages that are attached to the animal's back end. In a general sense, tail can also mean the back end of anything. Often, the phrase tail end is used.
My dog, Harvey, is bad at hiding his feelings. All dogs are, of course, but he is worse than most. When he wants something, he can't stop his tail from wagging.
Most students who are currently in high school were born at the tail end of the last century. In fact, they were born at the tail end of a millenium.
When we want to say that someone is engaged in an activity that rewards significant work with little progress, we say that he is chasing his tail. When someone is feeling shamed and embarrassed, we say that he has his tail between his legs.
I'd spent more than a month pursuing a theory that would help my thesis quite a bit, but got almost nothing I could use out of it. Figuring that I was just chasing my tail by that point, I gave it up and pursued other areas.
Feathers are what birds have instead of fur or scales. They are made of the same material as toenails.
This morning, I saw a hummingbird outside my window, flitting from flower to flower in a patch of honeysuckle. It had the most beautiful dark red feathers I've ever seen.
Marcus knew that his twin sons had been having pillow fights again, because there were feathers all over the floor.
There are many figurative expressions that use feather. If you have achieved an honor or accomplishment, it is a feather in your cap. Another is feathering your nest, which means taking advantage of opportunities for your own gain.
Jamie won an award from the English department of the high school for excellence in writing. It's a real feather in his cap, and will look great on his college applications.
I was stunned that Senator Desmond would take bribes. I'd gone to school with him and he had always seemed so honest, but here he was, feathering his nest with campaign contributions from people he had business relationships with in exchange for political favors.