red letter1
/ˌrɛd ˈlɛtə/noun
1A character or word written or printed in red, typically in order to draw attention to particularly important or significant information. Chiefly in plural.
- In earlier use, especially with reference to the convention of using red to indicate a saint's day or other Christian festival on an ecclesiastical calendar..
2A small moth, Agonopterix ocellana (family Oecophoridae), of Eurasia and North Africa, having a white spot ringed with red in the centre of the pale forewing. Also red-letter flat-body. rare.
Origin
Late Middle English; earliest use found in John Trevisa (c1342–?1402), translator. From red + letter.
red-letter2
/ˌrɛdˈlɛtə/verb
[with object] To mark out (a person or thing) for particular attention with, or as with, red letters.
- In earlier use: to canonize (a person)..
Origin
Late 18th century; earliest use found in John Gutch (1746–1831), antiquary and Church of England clergyman. From red letter.