∂
The character ∂ (html element: ∂ or ∂, unicode: U+2202) or is a stylized d mainly used as a mathematical symbol to denote a partial derivative such as (read as "the partial derivative of z with respect to x"). The symbol was originally introduced by Legendre in 1786, but only gained popularity when it was used by Jacobi in 1841.
∂ is also used to denote the following:
The symbol may be referred to as "del", "dee", "partial dee", "partial" (especially in LaTeX), "round d", "curly dee", or "dabba".
The lowercase Cyrillic De looks similar when italicized.
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