Unicode: F74C. Alias: Esc dd Esc. Compound operator with built-in evaluation rules.  can only be interpreted by default when it appears with ∫ or other integral operators. ∫ ...

Unicode: 2250. Alias: Esc .= Esc. Infix similarity operator. x ≐ y is by default interpreted as DotEqual[x,y]. Used to mean approximately equal, or in some cases, 'image of', ...

Unicode: 21D4. Alias: Esc <=> Esc. Infix arrow operator. x ⇔ y is by default interpreted as DoubleLeftRightArrow[x,y]. Used in mathematics to indicate logical equivalence. ...

Unicode: 2026. Alias: Esc ... Esc. Letter-like form. Used to indicate omitted elements in a row of a matrix. \[Ellipsis] on its own will act as a symbol.

Unicode: 25E6. Alias: Esc esci Esc. Letter-like form. Not the same as the infix operator \[SmallCircle]. Used as an overscript to add ring diacritical marks.

Unicode: 25B3. Letter-like form. Used in geometry to indicate a triangle, as in the symbol △ABC. Not the same as \[CapitalDelta].

Unicode: F7D4. Alias: Esc ent Esc. Letter-like form. Representation of the Enter key on a keyboard. Used in describing how to type textual input.

Unicode: 21CC. Alias: Esc equi Esc. Infix arrow-like operator. x ⇌ y is by default interpreted as Equilibrium[x,y]. Used in chemistry to represent a reversible reaction. ...

Unicode: F769. Alias: Esc ␣esc Esc. Letter-like form. Representation of the Escape key on a keyboard. Used in describing how to type aliases for special characters in ...

Unicode: 210F. Alias: Esc hb Esc. Letter-like form. Used in physics to denote Planck's constant divided by 2π; sometimes called Dirac's constant.