block vs close up

block is a noun but close up is not a noun.

Word	Noun	Adjective	Verb	Adverb
block	Yes	No	Yes	No
close up	No	No	Yes	Yes

As verbs, close up is a hypernym of block; that is, close up is a word with a broader meaning than block:

Other hypernyms of block include block, impede, jam, obstruct, obturate, occlude.

As verbs, block and close up are synonyms defined as:

Other synonyms of block include impede, jam, obstruct, obturate, occlude.

block (noun)	close up (noun)
the act of obstructing or deflecting someone's movements
a solid piece of something (usually having flat rectangular sides)
an obstruction in a pipe or tube
a simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope
a metal casting containing the cylinders and cooling ducts of an engine
a platform from which an auctioneer sells
housing in a large building that is divided into separate units
an inability to remember or think of something you normally can do; often caused by emotional tension
a number or quantity of related things dealt with as a unit
a rectangular area in a city surrounded by streets and usually containing several buildings
(computer science) a sector or group of sectors that function as the smallest data unit permitted
a three-dimensional shape with six square or rectangular sides

block (verb)	close up (verb)
shape into a block or blocks	refuse to talk or stop talking; fall silent
shape by using a block	block passage through
prohibit the conversion or use of (assets)	unite or bring into contact or bring together the edges of
be unable to remember	cease to operate or cause to cease operating
interfere with or prevent the reception of signals
impede the movement of (an opponent or a ball)
render unsuitable for passage
obstruct
stamp or emboss a title or design on a book with a block
support, secure, or raise with a block
block passage through
shut out from view or get in the way so as to hide from sight
interrupt the normal function of by means of anesthesia
hinder or prevent the progress or accomplishment of
stop from happening or developing
run on a block system

block (adverb)	close up (adverb)
	very close