n. 衬托物, 补偿物, 出发

[ noun ]
structure where a wall or building narrows abruptly
<noun.artifact>

Offset \Off"set`\, n. [Off + set. Cf. {Set-off}.]
In general, that which is set off, from, before, or against,
something; as:

1. (Bot.) A short prostrate shoot, which takes root and
produces a tuft of leaves, etc. See Illust. of
{Houseleek}.

2. A sum, account, or value set off against another sum or
account, as an equivalent; hence, anything which is given
in exchange or retaliation; a set-off.

3. A spur from a range of hills or mountains.

4. (Arch.) A horizontal ledge on the face of a wall, formed
by a diminution of its thickness, or by the weathering or
upper surface of a part built out from it; -- called also
{set-off}.

5. (Surv.) A short distance measured at right angles from a
line actually run to some point in an irregular boundary,
or to some object.

6. (Mech.) An abrupt bend in an object, as a rod, by which
one part is turned aside out of line, but nearly parallel,
with the rest; the part thus bent aside.

7. (Print.) A more or less distinct transfer of a printed
page or picture to the opposite page, when the pages are
pressed together before the ink is dry or when it is poor;
an unitended transfer of an image from one page to
another; called also {setoff}.
[1913 Webster +PJC]

8. See {offset printing}.
[PJC]

{Offset staff} (Surv.), a rod, usually ten links long, used
in measuring offsets.