alkaline

Etymology

It is formed from English alkali + -ine.^{[2][3][4][5][6]} Klein calls it a hybrid of alkali and a chemical suffix of Latin origin.^[7] The noun use follows New Latin alkalinum (1682), and the OED compares the earlier alcalinus (1533) and French alcalin (1691).^[2] Barnhart instead finds the word about 1330, in the phrase “sal alkalin”, perhaps borrowed from Medieval Latin independently of alkali.^[8] The noun alkali is from Medieval Latin alkali,^[8][3][2] which goes back to Arabic, where it named the ashes of saltwort.^[8][3][2]

Earliest recorded meaning

Having the properties of an alkali: 1682, in N. Grew's Anatomy of Plants.^[2][5] Etymonline and Dictionary.com date the word to the 1670s,^[3][6] and Barnhart finds it about 1330 in the phrase sal alkalin.^[8]

Semantic evolution

The word began in chemistry and was soon used as a noun for an alkaline substance (1684).^[2] Johnson (1755) defined it as "that which has the qualities of alkali".^[9] From 1789 it was used figuratively for something caustic or bitter, or for something soapy and soothing;^[2] from 1850, chiefly in the United States, of soil or land full of alkali or soluble salts.^[2][3] From 1888 it was used in geology of rocks and minerals rich in sodium and potassium.^[2] Since the late 20th century alkaline has also been a noun for an alkaline battery, dated 1969 by Merriam-Webster and 1980 by the OED.^[5][2]

Timeline

• 1682 – having the properties of an alkali.^[2][5] Etymonline dates the word to the 1670s.^[3]
• 1684 – noun, an alkaline substance.^[2]
• 1789 – figurative, caustic, bitter.^[2]
• 1850 – of soil, charged with alkali.^[2][3]
• 1888 – geology, of rocks rich in alkali metals.^[2]
• 1969 – noun, an alkaline battery.^[5] The OED dates this sense to 1980.^[2]

Meanings

Adjective

1. Having the properties of an alkali, or containing one; in chemistry, having a pH greater than 7: an alkaline solution.^{[5][10][2][4]}
2. Of soil or land, containing a lot of alkali or soluble salts.^[2][5]
3. (geology) Of rocks and minerals, rich in alkali metals such as sodium and potassium.^[2]
4. Figuratively, caustic or bitter.^[2]

Noun

1. An alkaline battery.^[5][2]
2. An alkaline substance.^[2]

Word family

• alkalinity
• alkalinize
• antalkaline
• alkaline battery
• alkaline earth
• alkaline earth metal
• alkaline phosphatase

Related words

• alkalescent
• alkalic
• alkali
• alkaloid

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t u v Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ a b c d e f g h Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
7. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
8. ^ a b c d Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
9. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
10. ^ Collins English Dictionary (2023), Glasgow: HarperCollins