horizon
/həˈraɪzən/noun
1
- usu. in sing. the line at which the earth's surface and the sky appear to meet地平线：
the sun rose above the horizon.
太阳从地平线上升起。
1.1
- （亦作apparent horizon）the circular boundary of the part of the earth's surface visible from a particular point, ignoring irregularities and obstructions视平线。
1.2
- （亦作true horizon）Astronomy a great circle of the celestial sphere, the plane of which passes through the centre of the earth and is parallel to that of the apparent horizon of a place【天文】地平圈。
2
- （常作horizons）the limit of a person's mental perception, experience, or interest视界, 眼界：
she wanted to leave home and broaden her horizons.
她想离开家, 开阔眼界。
3
- Geology a layer of soil or rock, or a set of strata, with particular characteristics【地质】地层。
3.1
- Archaeology a level of an excavated site representing a particular period【考古】层位。
短语
on the horizon
- just imminent or becoming apparent即将来临, 开始显现：
trouble could be on the horizon.
可能会有麻烦了。
词源
late Middle English: via Old French from late Latin horizon, from Greek horizōn （kuklos）'limiting (circle)'.