What has one letter and starts with an E?

I know a nine-letter word having only one vowel.
Do you ?

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

I am white when I am dirty, and black when I am clean. What am I?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

What has many keys but can’t open a single lock?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?