senior, seignior

Senior or senior means older or having more experience, as on a job--
He is five years senior to his brother, but he doesn't look it.
Mr. Jones is the senior clerk, and will be in charge while I'm away.

Senior may mean the elder of two persons with the same name--
I would like to speak to John Smith, Senior.

Senior may also mean one of the older students in a school, or a student in his or her last year--
He will be a senior next year, so he's applying to college.

Senior may also describe an old person, usually someone over the age of 65--
There's a senior citizen discount if you get there before 6 o'clock.

Seignior or seignior ( spelled seigneur in French ) means a lord or ruler--
He likes to play the grand seignior, distributing bounty to the peasants.
His father was the seignior of a great estate, but he is a wastrel.

Now that you know that, you can say--
"His brother is two years his senior, so he will be the next seignior of the manor."

Note--"señor" is Spanish for "Mister" or "sir"--
Excuse me señor, do you know where I can get a taxi?