形容詞 weighty:

1. having relatively great weight; heavy
2. powerfully persuasive
   同義詞：cogent, telling
3. of great gravity or crucial import; requiring serious thought
   同義詞：grave, grievous, heavy
4. weighing heavily on the spirit; causing anxiety or worry
5. excessively fat
   同義詞：corpulent, obese, rotund

1. Light grief speaks, the weighty is dumb.
   小悲傷喋喋不休; 大悲傷沉默寡言。
2. A weighty argument.
   有力的辯論

weight.y

adj.（形容詞）
weight.i.er,weight.i.est
Having considerable weight; heavy.See Synonyms at heavy
有相當?shù)闹亓康模恢氐膮⒁?heavy
Burdensome; oppressive:
難于負擔的；壓迫的：
例句：
weighty problems.
壓迫的問題

Of great consequence; momentous:
重要的；重大的：
例句：
the weighty matters before the delegates at the peace talks.
在和平談判中擺在代表們面前的重大事宜

Having great power or influence:
有力的，有影響的：
例句：
a weighty argument.
有力的辯論

Solemn; serious:
嚴肅的；認真的：
例句：
weighty music.
嚴肅音樂

【引伸】
weight.ily
adv.（副詞）
weight.iness
n.（名詞）