What does degassing mean?
Degassing refers to the process of removing dissolved, trapped, or otherwise unwanted gas from a substance or enclosure. The term appears across a wide range of fields: chemists degas solvents before sensitive reactions; metallurgists vacuum-degas molten steel to eliminate hydrogen that would cause cracking; manufacturers of resins, adhesives, and coatings degas mixtures under vacuum so no air bubbles mar the finished product; and coffee professionals speak of freshly roasted beans degassing carbon dioxide over several days, which is why roaster bags feature one-way valves. Degassing can be achieved by heating, applying a vacuum, stirring, sonicating, or simply allowing time for gas to escape. It can describe either a deliberate industrial operation or a natural passive release. Precise and technical but broadly applicable, degassing is essential vocabulary in chemistry, food science, manufacturing, and engineering, where controlling gas content directly affects quality, safety, and performance.
The removal of dissolved, trapped, or unwanted gas from a liquid, solid, or enclosed space by physical or chemical means.
"Vacuum degassing of the molten alloy prevented porosity in the finished casting."
Common in chemistry, metallurgy, food science, and manufacturing contexts.
The gradual release of gas from a substance, especially after processing or roasting.
"Coffee continues degassing for up to two weeks after roasting."
Present participle of 'degas': to remove gas from a substance or space.
"Technicians are degassing the solvent before the reaction begins."
Functions as both a verb form and a verbal noun.
Rarely used in plural form; degassing is almost always treated as an uncountable mass noun referring to the process rather than countable instances.
Fresh coffee beans 'degas' for days after roasting — which is exactly why your bag has a tiny one-way valve to let the carbon dioxide escape without letting oxygen in.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of degassing
Degassing derives from the noun 'gas', a term coined in the early seventeenth century by the Flemish chemist Jan Baptist van Helmont, who likely adapted it from Greek 'khaos' (chaos) — though some sources suggest influence from Dutch 'geest' (spirit). The prefix 'de-' indicates removal, forming the verb 'to degas' in the sense of extracting gas from something, with 'degassing' serving as its gerund and noun form. Related words sharing the root include 'gaseous', 'gasify', and 'gassy', all built on van Helmont's coinage.
Related word forms
How degassing is actually used
Degassing is a technical term most common in scientific, industrial, culinary, and engineering contexts. It is neutral in connotation and used in both British and American English. The related verb is 'to degas', with past forms 'degassed' and present participle 'degassing'.
Easily confused with degassing
Degaussing is the process of reducing or eliminating an unwanted magnetic field, whereas degassing is the removal of gas from a substance.