動詞 invoke:

1. summon into action or bring into existence, often as if by magic
   同義詞：raise, conjure, conjure up, evoke, stir, call down, arouse, bring up, put forward, call forth
2. cite as an authority; resort to
   同義詞：appeal
3. request earnestly (something from somebody); ask for aid or protection
   同義詞：appeal

1. The government has invoked the official secret act in having the book banned.
   政府援引國家機(jī)密保密法以禁該書。
2. They invoked help in the desperate situation.
   他們在走投無路的情況下懇求援助。

in.voke

v.tr.（及物動詞）
in.voked,in.vok.ing,in.vokes
To call on (a higher power) for assistance, support, or inspiration:
乞靈：祈求（一種更高的力量）給予幫助，支持，或靈感：
例句：
.Stretching out her hands she had the air of a Greek woman who invoked a deity.(Ford Madox Ford)
.她伸出她的雙手，就象一個希臘婦人祈求神靈一樣.(福特·馬多克斯·福特)

To appeal to or cite in support or justification.
授引：提出或授引…以支持或證明
To call for earnestly; solicit:
懇求：懇切地請求；懇請：
例句：
invoked the help of a passing motorist.
懇求一位過路的汽車司機(jī)給予幫助

To summon with incantations; conjure.
召鬼：用咒語喚來；召來鬼魂
To resort to; use or apply:
借助：求助于；使用或應(yīng)用：
例句：
.Shamelessly, he invokes coincidence to achieve ironic effect.(Newsweek)See Synonyms at enforce
.可恥的是，他借助于巧合來達(dá)到反諷效果.(新聞周刊)參見 enforce

來源：
Middle English envoken
中古英語 envoken
from Old French invoquer
源自 古法語 invoquer
from Latin invoc3re
源自 拉丁語 invoc3re
in- [in] * see in- 2
in- [在…里面] *參見 in-2
voc3re [to call] * see wek w-
voc3re [呼喚；叫] *參見 wek w-

【引伸】
invok.er
n.（名詞）