index vs symptom

index

noun
  • That which points out; that which shows, indicates, manifests, or discloses. 

  • An integer or other key indicating the location of data, e.g. within an array, vector, database table, associative array, or hash table. 

  • A sign; an indication; a token. 

  • The index finger; the forefinger. 

  • An alphabetical listing of items and their location. 

  • A movable finger on a gauge, scale, etc. 

  • A single number calculated from an array of prices or of quantities. 

  • A data structure that improves the performance of operations on a table. 

  • A raised suffix indicating a power. 

  • A symbol resembling a pointing hand, used to direct particular attention to a note or paragraph. 

  • A type of noun where the meaning of the form changes with respect to the context; e.g., 'Today's newspaper' is an indexical form since its referent will differ depending on the context. See also icon and symbol. 

  • A number representing a property or ratio; a coefficient. 

verb
  • To measure by an associated value. 

  • To inventory; to take stock. 

  • To be indexical for (some situation or state of affairs); to indicate. 

  • To arrange an index for something, especially a long text. 

  • To access a value in a data container by an index. 

  • To normalise in order to account for inflation; to correct for inflation by linking to a price index in order to maintain real levels. 

symptom

noun
  • A signal; anything that indicates, or is characteristic of, the presence of something else, especially of something undesirable. 

  • A perceived change in some function, sensation or appearance of a person that indicates a disease or disorder, such as fever, headache or rash; strictly, a symptom is felt or experienced by the patient, while a sign can be detected by an observer. 

How often have the words index and symptom occurred in a corpus of books? (source: Google Ngram Viewer )