What does labile mean?
Labile describes something that is inherently liable to change, especially something unstable, unsettled, or easily altered. The adjective is often used in technical writing, particularly in chemistry and biochemistry, where a labile bond, ligand, or group can be readily broken, replaced, or otherwise transformed. In broader contexts, it can characterize arrangements, relationships, or conditions that are vulnerable to change, such as political alliances or fluctuating circumstances. Its meaning is more forceful than simply saying that something may change: labile implies a pronounced readiness to change or an inherent instability. The word is formal and less common in everyday speech, but it is useful when precision is important because it distinguishes changeability that is intrinsic or especially easy from a merely possible or occasional alteration. The related noun lability is especially common in scientific and academic contexts.
adjectiveEasily changed, unstable, or liable to alteration. In chemistry, the term is used for bonds, groups, or compounds that readily undergo change, decomposition, or replacement.
- Easily changed, unstable, or liable to alteration.
- In chemistry, readily undergoing substitution, decomposition, or other chemical change.
"The molecule contains a labile bond that can be replaced under mild conditions."
"The labile hydrogen atoms could be exchanged for deuterium in a controlled reaction."
"Political alliances can be surprisingly labile when public opinion shifts."
In chemistry, a labile bond is not simply weak: it is one that can be broken or replaced with striking ease and precision.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does labile come from?
Labile comes through English from Latin lābilis, meaning “unstable” or “liable to slip or change.” The Latin word belongs to a family associated with the verb lābī, “to slip, glide, or fall,” which also underlies words such as lapse and collapse. The English adjective entered use in the 17th century and was later especially influential in chemical terminology.
Related word forms
How labile is actually used
The word is formal and relatively uncommon in general speech, but it is well established in chemistry and biochemistry. In general contexts, it suggests a quality that is unstable or readily changes rather than merely something that occasionally changes.
Easily confused with labile
Labile means inherently changeable or unstable, whereas liable usually means likely to experience something, especially a risk or obligation.
Labile means readily subject to change, while labial relates to the lips or to speech sounds produced with the lips.