respiration
n.the process of breathing. It is how living things take in oxygen and release carbon dioxide to get energy.
n.the biochemical process in which the cells of an organism obtain energy by combining oxygen and glucose, resulting in the release of carbon dioxide, water, and ATP.
“Exercise increases your rate of respiration.”
“The doctor monitored the patient's respiration to ensure they were getting enough oxygen during the procedure.”
“In aerobic respiration, oxygen acts as the final electron acceptor in the electron transport chain, a process that occurs within the mitochondria of eukaryotic cells.”
Uncountable when referring to the biological process; can be countable in medical contexts referring to a single breath.
“All living cells need energy, and most generate it through respiration, a series of chemical reactions normally confined to the cell membrane.”
“The team found that the amount of oxygen matches estimates of the respiration rates of microbes and animals across the North Atlantic deep sea.”
From Middle English respiracioun, borrowed from Latin respīrātiō, respīrātiōnem.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.