1
not used before a noun, US
a
: older in age
—usually + to
She is five years senior to me. = She is senior to me by five years. [=she is five years older than I am]
b
—used chiefly in its abbreviated form Sr. to identify a father who has the same name as his son.
John Smith, Jr. and John Smith, Sr.
2
: higher in standing or rank than another person in the same position
a senior officer/manager/executive
the senior vice president of marketing
She is a senior aide to the president.
a senior editor for the magazine
He recently became a senior partner in the accounting/consulting firm.
—often + toHe is senior to me.
3
always used before a noun
a
: of, relating to, or designed for older people
a senior center
senior housing
b
: designed for or done by adults or people over a certain age
the men's senior baseball league
senior golf
plural seniors
1
: a person who is older than another person
She is five years my senior. = She is my senior by five years. [=she is five years older than I am]
2
: a person who is of a higher rank than another person
As his senior, she commanded quite a bit of respect.
She was his senior in rank.
3
US
: a student in the final year of high school or college
high school juniors and seniors
—often used before another nounthe senior class/yearbook/prom
She skipped her senior year and went straight to college.
the senior captain of a team
4
chiefly US
: senior citizen
Cite this Entry
“Senior.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/senior. Accessed 20 Jun. 2026.
Copy Citation
