wane

名词 wane:

1. a gradual decline (in size or strength or power or number)
   同义词：ebb, ebbing

动词 wane:

1. grow smaller
   同义词：decline, go down
2. become smaller
3. decrease in phase

1. The empire was on the wane after its period of prosperity.
   帝国经过全盛以后逐渐衰落。
2. The moon waxes and wanes every month.
   月亮每个月都有盈亏。
3. By now the power of the Roman Empire was on the wane.
   到这时，罗马帝国已日益衰败。

wane

v.intr.（不及物动词）
waned,wan.ing,wanes
To decrease gradually in size, amount, intensity, or degree; decline.
衰落：体积、数量、密度或程度的逐渐减小；衰退
To exhibit a decreasing illuminated area from full moon to new moon.
（月）亏，缺：从满月到新月期间表现出逐渐减小的明亮区
To approach an end.
结束：到达终点
n.（名词）
The act or process of gradually declining or diminishing.
衰退：逐渐没落或减小的行为或过程

A time or phase of gradual decrease.
衰退期：逐渐衰退的时间或阶段
The period of the decrease of the moon`s illuminated visible surface.
月亏期：月亮的可见的明亮部分逐渐变小的时期
A defective edge of a board caused by remaining bark or a beveled end.
缺角方木：方木的由剩余树皮或斜角末端引起的缺损的边缘

<习惯用语>on the wane
In a period of decline or decrease:
衰减：处于正在衰退或减少的时期：
例句：
.The tide was near the turn and already the day was on the wane.(James Joyce)
.潮水即将退去，白昼渐渐消逝.(詹姆斯·乔伊丝)

来源：
Middle English wanen
中古英语 wanen
from Old English wanian * see eu- 2
源自 古英语 wanian *参见 eu- 2