1.
extremely large; enormous
An extremely large size or magnitude. Used as a no-adjective to describe something of the greatest possible size.
極大の被害。
Extremely large damage.
台風の影響は極大に達した。
The impact of the typhoon reached its maximum.
2.
local maximum; peak value
In mathematics and science, a point where a function reaches a peak relative to nearby values. Also used for the peak of astronomical events like meteor showers.
関数の極大値を求める。
To find the local maximum of a function.
ペルセウス座流星群は八月十二日ごろ極大を迎える。
The Perseid meteor shower reaches its peak around August 12th.
この関数にはx＝3で極大、x＝7で極小がある。
This function has a local maximum at x=3 and a local minimum at x=7.
太陽活動は約十一年周期で極大と極小を繰り返す。
Solar activity repeats a cycle of maximum and minimum roughly every eleven years.
A compound of 極 (extreme, pole) and 大 (large). Can function as a no-adjective: 極大の.
USAGE:
Sense 1 (extremely large) is used in general contexts but is fairly formal. Sense 2 (local maximum) is the more common technical usage, appearing in mathematics, physics, and astronomy. In astronomy, 極大 specifically refers to the peak of a periodic phenomenon such as a meteor shower or solar cycle.
COMMON COLLOCATIONS:
- 極大値 — maximum value (math)
- 極大を迎える — to reach a peak
- 極大期 — peak period
- 極大と極小 — maximum and minimum
SIMILAR WORDS:
- 最大 — greatest, largest; the absolute maximum (vs. 極大 which can be a local maximum)
- 極小 — minimum; extremely small; the antonym
- 極限 — limit, extreme; the furthest possible extent