粉线
划线

[ noun ]
a chalked string used in the building trades to make a straight line on a vertical surface
<noun.artifact>

Chalk \Chalk\ (ch[add]k), n. [AS. cealc lime, from L. calx
limestone. See {Calz}, and {Cawk}.]
1. (Min.) A soft, earthy substance, of a white, grayish, or
yellowish white color, consisting of calcium carbonate,
and having the same composition as common limestone.

2. (Fine Arts) Finely prepared chalk, used as a drawing
implement; also, by extension, a compound, as of clay and
black lead, or the like, used in the same manner. See
{Crayon}.

{Black chalk}, a mineral of a bluish color, of a slaty
texture, and soiling the fingers when handled; a variety
of argillaceous slate.

{By a long chalk}, by a long way; by many degrees. [Slang]
--Lowell.

{Chalk drawing} (Fine Arts), a drawing made with crayons. See
{Crayon}.

{Chalk formation}. See {Cretaceous formation}, under
{Cretaceous}.

{Chalk line}, a cord rubbed with chalk, used for making
straight lines on boards or other material, as a guide in
cutting or in arranging work.

{Chalk mixture}, a preparation of chalk, cinnamon, and sugar
in gum water, much used in diarrheal affection, esp. of
infants.

{Chalk period}. (Geol.) See {Cretaceous period}, under
{Cretaceous}.

{Chalk pit}, a pit in which chalk is dug.

{Drawing chalk}. See {Crayon}, n., 1.

{French chalk}, steatite or soapstone, a soft magnesian
mineral.

{Red chalk}, an indurated clayey ocher containing iron, and
used by painters and artificers; reddle.

chalk line \chalk" line`\ (ch[add]k" l[imac]n`), n.
1. a string impregnated with powdered chalk, used in
construction to mark a straight line on a surface, such as
a wall. The string is held taut on the surface between the
two end points of the line to be made, the center of the
line is drawn away from the surface, and the string is
released and snapped against the surface, leaving a line
of chalk in the desired location.
[PJC]

2. the line of chalk on a surface left by a {chalk line[1]}.
[PJC]