coma

• 该名词有几个意思：一种深度无意识状态，常由创伤或疾病引起；植物学上指苞片或毛组成的一簇；或彗核周围发光的由气体和尘埃组成的云状物。

A noun with multiple meanings: a state of deep unconsciousness often caused by injury or illness; a botanical tuft of bracts or hairs; or the luminous cloud of gas and dust surrounding a comet's nucleus.

1. Deep unconsciousnessB2formalmedical

   A state of deep and often prolonged unconsciousness, usually resulting from disease or injury.

   深度昏迷

   • The patient has been in a coma for three weeks after the accident.
   • Doctors are monitoring her brain activity while she remains in a coma.
   • He slowly emerged from the coma after the surgery.

   同义词insensibilitynarcosisoblivionsoporstuportorportranceunconsciousness

2. Botanical tuftC2formalscientific

   A usually terminal tuft of bracts (as in the pineapple) or tuft of hairs (especially on certain seeds).

   冠毛

   • The pineapple's coma consists of a cluster of small leaves at the top.
   • Certain seeds have a coma of fine hairs that aid in wind dispersal.
   • Botanists studied the coma of the dandelion seed for its aerodynamic properties.

   同义词crestpappustuft

3. Cometary cloudC2formalscientific

   The luminous cloud of particles surrounding the frozen nucleus of a comet; forms as the comet approaches the sun and is warmed.

   彗发

   • The coma of the comet became visible as it neared the sun.
   • Astronomers observed the expanding coma through powerful telescopes.
   • The comet's coma is composed of gas and dust particles.