Standing, not the job description
The daily job belongs to the sixth house. The tenth is the arc it adds up to and the reputation it produces. That distinction explains a common chart pattern: a demanding tenth with a light sixth describes someone known for something they do not actually work very hard at, and the reverse describes quiet competence nobody has noticed.
The Midheaven
The cusp of the tenth is the Midheaven, or MC, the highest point the ecliptic reached at your birth. In Placidus and most quadrant systems it is the tenth cusp exactly; in whole sign houses it floats and can land in the ninth or eleventh instead, which is one of the sharper practical differences between the systems.
Authority and the parent who represented it
Traditionally this house also covers the parent who dealt with the outside world, and by extension your relationship with authority in general. Whether you expect institutions to be reasonable, and how you behave when someone outranks you, is readable here more often than people expect.
Planets at the top of the chart
Anything within a few degrees of the Midheaven becomes a headline. A Sun there is hard to keep out of public view; Saturn there produces slow careers with durable standing; Neptune produces a public image that never quite comes into focus, which is either charisma or a nuisance depending on the field.
The fourth house beneath it
Tenth and fourth make the vertical axis: what the world sees against what only the household sees. The tension between them is the most common structural conflict in a chart, and it usually surfaces as an argument about how much of your life the work is entitled to.
The tenth house behaves differently in whole sign charts
In Placidus and the other quadrant systems the Midheaven is the tenth cusp by definition. In whole sign houses it is not: the tenth house is simply the tenth sign from the ascendant, and the Midheaven falls wherever the geometry puts it, most often in the ninth, tenth or eleventh.
This is not a technicality. A whole sign chart with the Midheaven in the ninth describes a career built on belief, teaching or distance, and that reading is unavailable in a Placidus chart of the same birth. It is worth casting both before drawing conclusions about someone's working life, and it is one of the clearer arguments for not treating any single house system as settled.
Questions people ask about this
Is the tenth house the same as the Midheaven?
In Placidus and other quadrant systems, yes, the Midheaven is the tenth cusp. In whole sign houses the Midheaven can fall in a different house entirely.
Does the tenth house say what job I should do?
It describes the kind of standing you are built for rather than a job title. The sixth house is closer to the daily reality of the work.
Do I need an exact birth time?
Yes. The Midheaven moves about a degree every four minutes.