1.
A symbol meaning "plus or minus" (or "give or take"), ± is used to denote the uncertainty in the value of a figure. It is primarily used in Physics experiments to account for any inaccuracy in the measuring/readings and any random errors that can occur which may affect the results obtained. However, it is also used in Engineering, Medicine, Chemistry, Mathematics and pretty much anythingwhere numbers and/or experimentation are used.
The symbol can be typed on a keyboard by pressing alt+753
(1.65 ± 0.05)m
(500 ± 5)mg/dose C9H8O4 was administered to patient X
See plus, minus, give, take, error, maths, mathematics, physics, chemistry, biology, science, engineering, academia, Necroyeti
2.
a plus sign with a line under it.
alt+753 a plus with a line inder it motherfucker
3.
this is a symbol used in maths to mean plus or minus
x = ± 78²-y
(not actual equation)
See -, +, algebra, alt codes