形容詞 head-on:

1. characterized by direct opposition
2. meeting front to front
   同義詞：frontal

副詞 head-on:

1. in direct opposition; directly
2. with the front foremost

1. The car hit the tree head-on.
   汽車迎面撞到樹上。

head-on

adv.（副詞）
With the head or front first:
正面地，頭對(duì)頭地：頭或前部在先地：
例句：
The cars crashed head-on.
汽車迎頭對(duì)撞

In open conflict; in direct opposition:
公開對(duì)抗地；直接反對(duì)地：
例句：
.I have wondered since whether it would have been wiser to meet the issue head-on.(Henry A. Kissinger)
.我為不知公然反對(duì)此事是否更為明智而感到疑惑.(亨利A.基辛格)

adj.（形容詞）
Facing forward; frontal.
向前的；正面的
With the front end foremost:
正面一端在前的：
例句：
a head-on collision.
正面沖撞