a.

1. 弱的，虛弱的；衰弱的
   She is still weak after her long illness.

   久病之後她仍很虛弱。

2. 軟弱的，懦弱的；優柔寡斷的
   He is a man of weak character.

   他這個人性格軟弱。

3. 淡的；稀薄的；無味的
4. （能力等）弱的，差的[（+at/in）]
   He was weak in mathematics, but good at English.

   他數學差，但英語好。

5. （論據等）不充分的，無說服力的
   The evidence he produced was very weak.

   他拿出的證據很不充分。

6. 【語】弱變化的；不重讀的[Z]
7. （價格）疲軟的

adj.

1. lacking physical strength and energy.
2. liable to break or give way under pressure.
   ▸not convincing or forceful.
   ▸not secure, stable, or firmly established.
   ▸(of prices or a market) having a downward tendency.
3. lacking power, influence, or ability.
   ▸lacking intensity.
   ▸(of a liquid or solution) heavily diluted.
   ▸(of features) not strongly marked.
   ▸(of a syllable) unstressed.
4. Grammar  denoting a class of verbs in Germanic languages that form the past tense and past participle by addition of a suffix (in English, typically -ed).