awful

afraid, fearful, awful, dreadful, frightful, terrible, horrible, terrific, appalling

形容词 awful:

1. exceptionally bad or displeasing
   同义词：atrocious, abominable, dreadful, painful, terrible, unspeakable
2. causing fear or dread or terror
   同义词：dire, direful, dread, dreaded, dreadful, fearful, fearsome, frightening, horrendous, horrific, terrible
3. offensive or even (of persons) malicious- Ezra Pound
   同义词：nasty
4. inspired by a feeling of fearful wonderment or reverence
   同义词：awed
5. extreme in degree or extent or amount or impact
   同义词：frightful, terrible, tremendous
6. inspiring awe or admiration or wonder
   同义词：amazing, awe-inspiring, awesome, awing

副词 awful:

1. used as intensifiers
   同义词：terribly, awfully, frightfully

1. It would be awful if he found out the truth.
   如果他发现了真相，那就糟了。
2. It was awful to see him in such pain.
   看到他这样痛苦真叫人难过。

aw.ful

adj.（形容词）
Extremely bad or unpleasant; terrible:
可怕的，厉害的：极糟糕的或令人不愉快的；可怕的：
例句：
had an awful day at the office.
在办公室里度过了糟糕的一天

Commanding awe:
畏惧的：
例句：
.this sea, whose gently awful stirrings seem to speak of some hidden soul beneath.(Herman Melville)
.大海有些令人畏惧的波动似乎在诉说着隐藏在下面的热情.(赫尔曼·梅尔维尔)

Filled with awe, especially:
充满敬畏的：充满敬畏的，尤指：
Filled with or displaying great reverence.
虔敬的：充满或表现出极大的敬重的
Obsolete Afraid.
【废语】 恐惧的
Formidable in nature or extent:
艰难的：在性质或程度上令人畏惧的：
例句：
an awful burden; an awful risk.
艰难的重担；可怕的冒险

adv.Informal （副词）【非正式用语】
Extremely; very:
极度地；非常：
例句：
was awful sick.
病得很重

来源：
Middle English aweful [awe-inspiring]
中古英语 aweful [引起畏惧的]
blend of awe [awe] * see awe
混合了 awe [害怕的] *参见 awe
*ayfull [awful] from Old English egefull ege [dread] -full [-ful]
*ayfull [畏惧的] 源自 古英语 egefull ege [害怕；惧怕] -full [后缀，表充满…的或易于…的]

【引伸】
aw.fully
adv.（副词）
aw.fulness
n.（名词）