the lowercase delta symbol, , is used for ‰ (per mil) deviation from a standard; whereas uppercase delta, , is used as the measurement of the difference between a product and a reactant.

D d Fourth Letter of the Greek Alphabet. The font "Symbol" most often used on American Computers to Type Cyrillic Letters places it in ASCII 67- the space for capital "C" .It looks just like an "A" with the crossbar dropped to the baseline.

the 4th letter of the Greek alphabet

The upper-case Greek letter used to denote an object's geocentric distance in ephemeris tables; see "ephemeris". (Note that lower-case delta is used to denote declination.)

A Greek symbol used to express a difference between two terms. For example, D H means that the variable H is the difference of two other terms such as H1 and H2.

military phonetic for the letter 'D'

Military phonetic term for the latter D Distance from target in # yards

Delta (uppercase Δ, lowercase δ) is the fourth letter of the Greek alphabet. In the system of Greek numerals it has a value of 4. It was derived from the Phoenician letter Dalet .