While we are accustomed to using left and right with regard to politicians and political ideas, it is interesting to look at some other concepts about these two words.
Left:
The English word “left” comes from the Old English *lyft which meant “weak” or “foolish.” It wasn’t until the thirteenth century that “left” came to be used as the partner for “right.”
In Old English, the word for “left” was “winestra” which has a deeper meaning of “friendlier.” Keeping in mind that the left-hand side of the body has often been associated with ill-omens, using “friendlier” in referring to this side of the body was an attempt to placate the evil forces of the left.
In the past, people who were left-handed were thought to be sneaky, evil, strange, and clumsy. There were even some who thought that left-handed people were the children of the Devil. Left-handed children and their mothers were to be shunned. The left side of the body was associated with darkness, ineptitude, and ill-fortune.
There are lots of old superstitions associated with the left side of the body:
Stepping off of the sleeping mattress with the left foot first is felt to invite disaster. That is, it is getting out of bed on the wrong side.
When your left palm itches, you are about to lose money.
The Prince of Darkness sits on God’s left, an indicator that evil is on the left.
When someone is a poor dancer, it is often said that they have two left feet. In other words, left is associated with being clumsy and awkward.
A thinly veiled insult is called a left-handed compliment.
Right:
The English word “right” can be traced back to the Indo-European base *reg- which means “to move in a straight line.” The use of “right” to mean the opposite of “left” comes from the idea that the right hand is the “correct” hand to use.
In ancient times, the right side of the body was felt to be associated with good and virtue. The Archangel Michael, for example, sits on God’s right hand. When a man is a good helper, he is called a right-hand man.
The English word “dexterous” comes from the Latin word “dexter” which means “right.” Thus, an ambidextrous person has two right hands (two hands which are “good”).
The use of “right” referring to the politically conservative actually comes from the French Revolution. In the French National Assembly of 1789 the nobles sat to the right of the president and the commoners sat on the left. Since the nobles (i.e. the wealthy) were more interested in maintaining their economic and social status, those who sat on the right were more conservative. Hence “right” came to mean “conservative.”
Note: the * indicates that the Indo-European or prehistoric word has been reconstructed by historical linguists.