Packing vs Undefined - What's the difference?

As a verb packing

is .

is the action of the verb.

lacking a definition or value.

(head)

* send someone packing

(en noun)

The action of the verb.

# The action of putting things together, especially of putting clothes into a suitcase for a journey.

# (sciences, mathematics) The spatial arrangement of objects, items or constituent parts.

# The gathering of birds, animals etc. into a pack.

# (rugby) The forming of players into a scrum.

As a concrete noun.

# Material used to fill in the space around something, especially to make a piston etc. watertight or airtight.

# Material used to wrap a product for sale etc.; packaging.

# A fee charged to cover the costs of packaging.

# Special material used to fill containers or vessels for certain chemically related applications.

::::*Examples: Packing in a packed bed, or a column such as a distillation column or a chromatography column

* packing case

(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