Pennant vs Undefined - What's the difference?

As a noun pennant

is a flag normally used by naval vessels to represent a special condition.

lacking a definition or value.

(en noun)

A flag normally used by naval vessels to represent a special condition.

# The broad pennant flown by commodores.

# The church pennant indicating religious services are taking place aboard ship.

# The commissioning pennant flown on ceremonial occasions.

(sports) The winning of a competition, represented by a flag.

The New York Yankees have won the American League pennant far more often than any other team.

A rope or strap to which a purchase is hooked.

Not to be confused with pedant (one overly concerned with correctness), nor with pendant (a piece of jewellery).

(wikipedia undefined) (-)

Lacking a definition or value.

(mathematics, computing) That does not have a meaning and is thus not assigned an interpretation.

The result of division by zero is undefined .

* defined