senior
Definition
Higher in rank, status, or age; more advanced or experienced, as in a 'senior manager' who outranks the interns.
Pertaining to the final year of high school or college, when students are one step away from freedom (or debt).
A person of greater age or authority, often shorthand for 'senior citizen' who remembers rotary phones fondly.
As a noun, an elder or high-ranking individual who dispenses wisdom—or naps through meetings.
Examples
The senior developer fixed the bug in five minutes, then spent the rest of the day explaining it to the juniors like a cryptic riddle.
As a high school senior, she treated every college application like a job interview for adulthood, complete with rehearsed enthusiasm.
My senior neighbor outruns me on the treadmill and claims it's all from chasing grandkids—or dodging telemarketers.
He's the senior partner at the firm, which means he arrives late, delegates everything, and still takes credit for the coffee run.