Définitions
1.NounA bond or tie that unifies.
2.NounAny symbol used to group some of the terms in an expression, indicating that that part of the calculation should be done before other parts, or that the Roman numeral underneath should be multiplied by 1,000.
3.NounA horizontal line over the top of some of the terms in an expression, indicating that that part of the calculation is to be done before other parts (in modern mathematical notation confined to use in radicals:
x
+
y
{\displaystyle {\sqrt {x+y}}}
).
4.NounThe horizontal line between the numerator and denominator in a fraction.
5.NounA horizontal line placed over one or more digits of a decimal expansion to indicate that those digits repeat indefinitely (the repetend)."
0.
3
¯
=
0.333
…
{\displaystyle 0.{\overline {3}}=0.333\ldots }
"
6.NounA horizontal line placed over a complex number or expression to denote its complex conjugate."
2
+
3
i
¯
=
2
−
3
i
{\displaystyle {\overline {2+3i}}=2-3i}
"
7.NounA horizontal line drawn over two letters to denote the line segment joining them."
A
B
¯
{\displaystyle {\overline {AB}}}
is the line segment between points
A
{\displaystyle A}
and
B
{\displaystyle B}
"
8.NounA horizontal line placed over a symbol or expression to denote logical negation (complement)."
A
¯
=
¬
A
{\displaystyle {\overline {A}}=\lnot A}
;
A
B
¯
=
¬
(
A
∧
B
)
{\displaystyle {\overline {AB}}=\lnot (A\land B)}
"
9.NounA horizontal line placed over the characteristic (integer part) of a common logarithm to indicate that the characteristic is negative while the mantissa (decimal part) remains positive. Historically used to simplify the use of logarithm tables."
log
0.012
=
2
¯
.07918
=
−
1.92082
{\displaystyle \log 0.012={\overline {2}}.07918=-1.92082}
"
10.NounA ligament that limits the movement of an organ or part.
11.NounA symbol in the shape of an elongated letter "S" (∫) or pair of hooks (⌠⌡) drawn on plans to join non-contiguous sections of land that are to be treated as a single parcel.