動(dòng)詞 obligate:

1. force or compel somebody to do something
   同義詞：compel, oblige
2. commit in order to fulfill an obligation
3. bind by an obligation; cause to be indebted
   同義詞：oblige, bind, hold

形容詞 obligate:

1. restricted to a particular condition of life

1. He felt obligated to help.
   他覺(jué)得有責(zé)任予以幫助。
2. We were obligated to attend the opening ceremony.
   我們有必要參加開(kāi)幕式。

ob.li.gate

v.tr.（及物動(dòng)詞）
ob.li.gat.ed,ob.li.gat.ing,ob.li.gates
To bind, compel, or constrain by a social, legal, or moral tie.See Synonyms at force
使負(fù)有責(zé)任或義務(wù)：被社會(huì)、法律或道德約束所束縛，強(qiáng)制或限制參見(jiàn) force
To cause to be grateful or indebted; oblige.
使…感激或感謝；施恩惠于
To commit (money, for example) in order to fulfill an obligation.
承擔(dān)（如，錢(qián)）以履行義務(wù)
adj.（形容詞）

Biology Able to exist or survive only in a particular environment or by assuming a particular role:
【生物學(xué)】 專性的，固性的：只能在一種特定環(huán)境下或通過(guò)承擔(dān)一種特定角色而存在或生存的：
例句：
an obligate parasite; an obligate anaerobe.
專性寄生蟲(chóng)；專性厭氧生物

Absolutely indispensable; essential.
必不可少的；根本的

來(lái)源：
Latin oblig3re oblig3t- * see oblige
拉丁語(yǔ) oblig3re oblig3t- *參見(jiàn) oblige

【引伸】
ob.ligable
ob.ligately
adv.（副詞）
ob.liga.tor
n.（名詞）