Ant in one’s pants
People who have ants in their pants are very restless or excited about something.
The term eager beaver refers to a person who is hardworking and enthusiastic, sometimes considered overzealous.
Bee in one’s bonnet
Someone who has a bee in their bonnet has an idea which constantly occupies their thoughts.
Birds of a feather flock together
If two people are birds of a feather, they are very similar in many ways, so they naturally spend time together.
A dark horse
Someone who is more clever or skilful than anyone expects
A lone wolf
Someone who is not very social with other people
A guinea pig
Someone who is part of an experiment or trial
The travel bug
A very strong desire to travel
To have butterflies in your stomach
To be nervous
An early bird
A person who gets up early in the morning, or who starts work earlier than others.
A home bird
Somebody who prefers to spend his social and free time at home.
A busy bee
A busy, active person who moves quickly from task to task.
A lone bird/ wolf
Someone who prefers his won company or who has little social contact with others.
An odd bird/ fish
An eccentric person whose behavior or way of life is regarded as strange.
A rare bird
Somebody or something of a kind that one seldom sees.
A dog in the manger
A person who selfishly prevent others from using, enjoying or profiting from something even though he/ she cannot use or enjoy it himself.
A cold fish
Somebody who is not often moved by emotions, who is regarded as being hard and unfeeling.
A dark horse
Someone whose past is a mystery; a person who keeps their interests and ideas secret, especially someone who has a surprising ability or skill.
A lame duck
A person or enterprise (often a business) that is not a success and that has to be helped.
A sitting duck
An easy target.