also: やた
eight ata (approx. 144 cm)
Only with reading やあた
Archaic unit of length; 1 ata (咫) is the distance between the tips of the thumb and middle finger when spread, roughly 18 cm. Eight ata is about 144 cm. Used in historical contexts, especially in reference to the mythical sword 八咫鏡 (Yata no Kagami).
See also: 咫
The Yata no Kagami is said to be a mirror of eight ata in size.
Only with reading やた
Used in classical or mythological contexts to describe something of great size or length, often in fixed expressions like 八咫烏 (Yatagarasu, the three-legged crow). The reading is usually やた.
The Yatagarasu is a large crow that appears in mythology.
咫 is the base unit of length (about 18 cm); 八咫 is a specific measurement of eight such units, and also used figuratively for 'large'.
Standard kanji form; reading やた is usual for the 'large' sense, while やあた is an older reading for the measurement sense.
Archaic reading used specifically for the historical measurement sense.
Compound of 八 (ya, 'eight') and 咫 (ata, an ancient unit of length). The figurative sense 'large' derives from the notion of something being eight ata in size, implying great magnitude.