face vs take on

face is a noun but take on is not a noun.

Word	Noun	Adjective	Verb	Adverb
face	Yes	No	Yes	No
take on	No	No	Yes	No

As verbs, take on is a hyponym of face; that is, take on is a word with a more specific, narrower meaning than face:

Other hyponyms of face include tackle, undertake.

As verbs, take on is a hypernym of face; that is, take on is a word with a broader meaning than face:

Other hypernyms of face include encounter, meet, play.

face (noun)	take on (noun)
a vertical surface of a building or cliff
the side upon which the use of a thing depends (usually the most prominent surface of an object)
the striking or working surface of an implement
the general outward appearance of something
status in the eyes of others
impudent aggressiveness
the feelings expressed on a person's face
the front of the human head from the forehead to the chin and ear to ear
the part of an animal corresponding to the human face
a specific size and style of type within a type family
a contorted facial expression
a surface forming part of the outside of an object
a part of a person that is used to refer to a person

face (verb)	take on (verb)
deal with (something unpleasant) head on	take on a certain form, attribute, or aspect
present somebody with something, usually to accuse or criticize	contend against an opponent in a sport, game, or battle
oppose, as in hostility or a competition	admit into a group or community
line the edge (of a garment) with a different material	accept as a challenge
cover the front or surface of	take on titles, offices, duties, responsibilities
turn so as to face; turn the face in a certain direction
turn so as to expose the face
be oriented in a certain direction, often with respect to another reference point; be opposite to
be opposite