Underdone describes food that hasn't finished cooking. Sometimes food is underdone on purpose.
Uis forUndergrowth
Uis forUnderneath
Underneath is a more interesting way of saying under. The cat in the picture is underneath a coffee table.
Uis forUndershirt
Uis forUnderweight
A person or animal is underweight if they weigh less than they should. When you are underweight you can easily see your bones.
Uis forUnfinished
Something is unfinished if it has not been completed yet.
A similar word to unfinished is incomplete.The opposite of unfinished is finished.
Someone is unfit if they are in poor physical condition, and get tired very easily when they do physical activity. The man in the photo is very unfit.
Unfit also means something that doesn't suit a purpose, for example a rotten fruit is unfit to eat.