turnsole

turnsole

A gardener plants a turnsole in the sunny flowerbed.

Definition

Noun: 1. A plant of the genus Heliotropium: "turnsole" refers to any of various plants, especially those in the heliotrope family, known for turning their flowers toward the sun. - The turnsole is often called "heliotrope" because of its sun-tracking habit. 2. A dye obtained from such plants: Historically, "turnsole" also denotes a purple or blue dye extracted from certain plants (e.g., Chrozophora tinctoria), used as a chemical indicator (like litmus). - In medieval times, turnsole was used to color manuscripts and as a pH test. 3. The common sunflower (Helianthus annuus): In some contexts, "turnsole" is a synonym for the sunflower, which follows the sun's movement. - The turnsole’s large yellow head faces east in the morning and west by evening.

Usage Examples
  • (A heliotrope plant.)
  • (A dye from the plant.)
  • (Referring to the sunflower.)
Advanced Usage
  • "turnsole paper": paper treated with turnsole dye, used as a pH indicator (similar to litmus paper).
    • The teacher demonstrated acid-base reactions using turnsole paper, which turned red in acid and blue in alkali.
Variants and Related Words
  • Turnsol (n): an alternate spelling, especially in historical texts.
    • The term "turnsol" appears in 16th-century herbals.
  • Heliotrope (n): a synonym for turnsole plants.
    • The heliotrope is also known as the turnsole due to its sun-following behavior.
Synonyms
  • Sunflower: a common name for , often called turnsole.
  • Heliotrope: a plant of the genus .
  • Litmus: a dye derived from lichens, but sometimes confused with turnsole in historical chemistry.
Related Idioms
  • "Turnsole of the sun": a poetic phrase referring to something that follows or reflects a guiding force.
    • She was the turnsole of his affections, always orienting toward his presence. (A metaphorical use, not common in modern English.)