As nouns the difference between steer and seg
is that steer
is the castrated male of cattle, especially one raised for beef production or steer
can be (informal) a suggestion about a course of action or steer
can be (obsolete) a helmsman; a pilot while seg
is (archaic) a man; warrior; hero or seg
can be (uk|scotland|dialect) a castrated bull or seg
can be segregation or seg
can be a metal stud or plate fixed to the sole or heel of a shoe to prevent excessive wear also known as a blakey or seg
can be sedge.
As a verb steer
is to castrate (a male calf) or steer
can be to guide the course of a vessel, vehicle, aircraft etc (by means of a device such as a rudder, paddle, or steering wheel).