Ignoble (adjective)

1. Not noble in character or quality; dishonorable; base.
2. Not of a high social, moral, or intellectual rank; common.

Origin:

Late middle english: from old french, or from latin ignobilis, from in- "not" + gnobilis "well-known, noble".

Examples:

1. His ignoble actions brought shame to his family.
2. An ignoble act is one that is not honorable or is dishonorable.
3. The ignoble behavior of the politicians brought the whole system into disrepute.
4. It is ignoble to cheat or steal, even if it's for a good cause.
5. He was an ignoble character who only cared about himself and his own interests.