work vs specialize

work is a noun but specialize is not a noun.

Word	Noun	Adjective	Verb	Adverb
work	Yes	No	Yes	No
specialize	No	No	Yes	No

As verbs, specialize is a hyponym of work; that is, specialize is a word with a more specific, narrower meaning than work:

work: exert oneself by doing mental or physical work for a purpose or out of necessity; work
specialize: devote oneself to a special area of work

work (noun)	specialize (noun)
activity directed toward making or doing something
the occupation for which you are paid
a product produced or accomplished through the effort or activity or agency of a person or thing
a place where work is done
the total output of a writer or artist (or a substantial part of it)
applying the mind to learning and understanding a subject (especially by reading)
(physics) a manifestation of energy; the transfer of energy from one physical system to another expressed as the product of a force and the distance through which it moves a body in the direction of that force

work (verb)	specialize (verb)
give a workout to	become more focused on an area of activity or field of study
arrive at a certain condition through repeated motion	suit to a special purpose
go sour or spoil	evolve so as to lead to a new species or develop in a way most suited to the environment
cause to undergo fermentation	be specific about
find the solution to (a problem or question) or understand the meaning of	devote oneself to a special area of work
use or manipulate to one's advantage
to mix into a homogeneous mass
perform as expected when applied
move into or onto
shape, form, or improve a material
cause to happen or to occur as a consequence
prepare for crops
make something, usually for a specific function
gratify and charm, usually in order to influence
proceed along a path
move in an agitated manner
provoke or excite
be employed
cause to work
exert oneself by doing mental or physical work for a purpose or out of necessity; work
have an effect or outcome; often the one desired or expected
operate in a certain place, area, or specialty
proceed towards a goal or along a path or through an activity
have and exert influence or effect
operate in or through
cause to operate or function
behave in a certain way when handled