形容詞 halfway:

1. equally distant from the extremes
   同義詞：center, middle, midway
2. at a point midway between two extremes
3. including only half or a portion

副詞 halfway:

1. at half the distance; at the middle
   同義詞：midway

1. Halfway through the race the horse went lame.
   那匹馬賽跑中途跛了腿。
2. The key turned halfway and then jammed.
   鑰匙轉(zhuǎn)了一半就卡住了。
3. We had a short intermission halfway through a film.
   我們電影放映中途做了短暫的休息。

half.way

adj.（形容詞）
Midway between two points or conditions:
在半路上或在中間狀態(tài)：
例句：
a halfway sign on the trail.
鐵軌上的半程標(biāo)記

Reaching or including only half or a portion; partial:
僅到達(dá)一半或一部分的；不完全的：
例句：
halfway measures.
不完全的措施

【引伸】
half.way.
adv.（副詞）