block out

1 of 2

transitive verb

1

: to shut from view : screen

that vine on the porch blocks out all the sunlight

:

a

: to prevent (a part of a photographic negative) from printing by painting over with opaque or a comparable substance

b

: to cancel (printed matter) by overprinting with a solid patch of ink

2

a

: to excavate (something, such as ore and gravel) by making a drive in the wall and taking out the material in blocks or strips along the sides of the drive

b

: to subdivide (a lode) into blocks in advance of the working stopes by shafts, winzes, and intersecting drives or levels so as to be ready for stoping and to keep a known amount of reserve ore in sight

blockout

2 of 2

noun

plural -s

: a reproduction (such as a photographic negative or a halftone) of which a part has been blocked out

Word History

Etymology

Noun

block out

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