動(dòng)詞 envelop:

1. enclose or enfold completely with or as if with a covering
   同義詞：enfold, enwrap, wrap, enclose

1. The building was soon enveloped in flames.
   那幢建筑物很快就陷入了火海之中。
2. The papers are falling out of the envelop, push them back.
   論文從封袋里掉出來(lái)了，把它們放回原處。

en.vel.op

v.tr.（及物動(dòng)詞）
en.vel.oped,en.vel.op.ing,en.vel.ops
To enclose or encase completely with or as if with a covering:
包?。河没蚝孟笥谜谏w物完全包住或圍住：
例句：
.Accompanying the darkness, a stillness envelops the city.(Curtis Wilkie)
.隨著黑暗的降臨，靜寂籠罩了城市.(柯蒂斯·威爾基)

To attack (an enemy`s flank).
攻擊（敵軍側(cè)翼）

來(lái)源：
Middle English envolupen [to be involved in]
中古英語(yǔ) envolupen [被卷入]
from Old French envoluper, envoloper
源自 古法語(yǔ) envoluper, envoloper
en- [in] * see en-
en- [在…里面] *參見 en-
voloper [to wrap up]
voloper [包裹起來(lái)]

【引伸】
envel.oper
n.（名詞）
envel.opment
n.（名詞）