sequential

Etymology

It is formed from English sequence + -al, on the pattern of consequential,^[2][3] or directly from Late Latin sequentia (“sequence”) with the English suffix.^[4][5][6] Dictionary.com takes it from sequent and -ial.^[7] The Latin noun is formed from sequēns, the present participle of sequor (“to follow”), the source of sequence.^[5]

Earliest recorded meaning

In medicine, following as a secondary condition after an earlier disease: 1822, in J. M. Good's Study of Medicine.^[4][6][3] Etymonline dates the general sense, "following in succession", to 1816,^[5] and Dictionary.com dates the word to 1815–25.^[7]

Semantic evolution

The medical sense, a sequela, was the first; the general sense of forming a sequence followed in 1854, and "characterized by the regular sequence of its parts" in 1844.^[4][2] In the 20th century the word was taken up by several technical fields: computing, for operations carried out one after another (1951), television scanning and colour systems (1940s) and electronics, for logic circuits whose output depends on the order of the inputs (1954).^[4]

Timeline

• 1822 – in pathology, following as a secondary disease.^[4]
• 1844 – characterized by a regular sequence of parts; continuous.^[4]
• 1854 – following as a sequel; of several things, forming a sequence.^[4]
• 1899 – resultant, consequent.^[4]
• 1951 – in computing, operating serially.^[4]
• 1954 – in electronics, of a logic circuit depending on the order of its inputs.^[4]

Meanings

Adjective

1. Forming or following a sequence; consecutive or serial: The tickets have sequential numbers.^[6][8][4]
2. Arranged in a regular, logical order: a sequential account of events.^[6][4]
3. In medicine, occurring as a sequela of an earlier disease or injury.^[6][4]
4. In computing, operating on or reading data one item after another, in order.^[4][6]

Word family

• sequentiality
• sequentially

Related words

• sequence
• sequent
• consequential
• sequel
• sequela

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
3. ^ a b Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
4. ^ a b c d e f g h i j k l m n Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ Collins English Dictionary (2023), Glasgow: HarperCollins