CO2

 Dictionary entry overview: What does CO2 mean? 

• CO2 (noun)
  The noun CO2 has 1 sense:

1. a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis

  Familiarity information: CO2 used as a noun is very rare.

 Dictionary entry details 

• CO2 (noun)

Sense 1

Meaning:

A heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis

Classified under:

Nouns denoting substances

Synonyms:

carbon dioxide; carbonic acid gas; CO2

Hypernyms ("CO2" is a kind of...):

dioxide (an oxide containing two atoms of oxygen in the molecule)

greenhouse emission; greenhouse gas (a gas that contributes to the greenhouse effect by absorbing infrared radiation)

Hyponyms (each of the following is a kind of "CO2"):

blackdamp; chokedamp (the atmosphere in a mine following an explosion; high in carbon dioxide and incapable of supporting life)

 Context examples 

Last year’s global CO2 average reached 399 ppm, meaning that the global average in 2016 will almost certainly surpass 400 ppm.

(South Pole is last place on Earth to pass global warming milestone, NOAA)

They found that earlier snowmelt triggered by climate change reduces forests' ability to take CO2 out of the atmosphere.

(Earlier snowmelt decreases streamflow, reduces forests' ability to regulate atmospheric carbon dioxide, NSF)

In 2015, the global average carbon dioxide (CO2) concentration reached 399 parts per million (ppm), increasing by a record amount of almost 3 ppm.

(Warming due to carbon dioxide jumped by half in 25 years, NOAA)

In a series of reactions two carbons in citrate are oxidized to CO2 and the reaction pathway supplies NADH for use in the oxidative phosphorylation and other metabolic processes.

(Citrate Cycle (TCA Cycle) Pathway, NCI Thesaurus/KEGG)

Upon determination of the ratio between 13C/12C of CO2 in exhaled breath, liver function can be assessed.

(Carbon C 13 Sodium Octanoate, NCI Thesaurus)

The acetyl-CoA generated in beta-oxidation enters the Krebs cycle, where it is further oxidized to CO2, producing more reduced energy carriers, NADH and FADH2 (See Krebs cycle pathway).

(Beta-Oxidation of Fatty Acids Pathway, NCI Thesaurus/BIOCARTA)

The study used data from the Community Earth System Model (CESM) to forecast ocean acidification under several CO2 emission assumption scenarios, looking at changes in calcium carbonate saturation.

(Marine organisms in Southern Ocean will face shallower zone for life, National Science Foundation)

Current global vegetation models have faced challenges in producing consistent estimates of plant CO2 uptake, scientists say.

(What's killing trees during droughts?, National Science Foundation)

To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable.

(Scientists Turn CO2 into Solid Coal, The Titi Tudorancea Bulletin)

The reverse occurs when those organisms die: microbes start to decompose, consuming oxygen and releasing CO2 back into the air.

(Carbon hides in sediment, keeping oxygen in atmosphere, National Science Foundation)