Subscript

adj. written below (of a distinguishing character)

n. distinguishing symbol written below a letter or number

This article is about the terms 'subscript' and 'superscript' as used in typography. "SuperScript" can also refer to a commercially available Reverse transcriptase.A subscript or superscript is a number, figure, symbol, or indicator that appears smaller than the normal line of type and is set slightly below or above it – subscripts appear below the baseline, while superscripts are above. Subscripts and superscripts are typically used in formulas, mathematical expressions, and descriptions of chemical compounds or isotopes, but have many other uses as well.
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Noun
1. a character or symbol set or printed or written beneath or slightly below and to the side of another character
(synonym) inferior
(antonym) superscript, superior
(hypernym) character, grapheme, graphic symbol
Adjective
1. written or printed below and to one side of another character
(synonym) inferior
(antonym) adscript
(classification) printing, printing process

(n.)
Anything written below.
  

(a.)
Written below or underneath; as, iota subscript. (See under Iota.) Specifically (Math.), said of marks, figures, or letters (suffixes), written below and usually to the right of other letters to distinguish them; as, a, n, 2, in the symbols Xa, An, Y2. See Suffix, n., 2, and Subindex.
  

Synonyms and related words:
PS, Parthian shot, addendum, afterthought, appendix, back matter, chorus, coda, codicil, colophon, conclusion, consequence, continuance, continuation, double take, dying words, envoi, epilogue, follow-through, follow-up, last words, parting shot, peroration, postface, postfix, postlude, postscript, refrain, second thought, sequel, sequela, sequelae, sequelant, sequent, sequitur, suffix, supplement, swan song, tag