labile

Labile is an adjective meaning easily altered, unstable, or prone to fluctuation. In scientific usage it describes states, substances, or processes that do not maintain a fixed condition and may change rapidly under ordinary conditions.

In chemistry and biochemistry, a labile compound readily undergoes chemical change or exchanges components. Ligand exchange in coordination chemistry or hydrolysis in aqueous environments can be described as labile. By contrast, inert or kinetically inert species resist change and exchange.

In biology and histology, labile tissues are those that renew themselves continuously, such as the epithelium, bone marrow, and the intestinal lining. Stable tissues renew more slowly, and permanent tissues have little to no regenerative capacity, such as certain neurons and cardiac muscle.

In medicine and psychology, labile describes unstable or highly variable states. Emotional lability refers to rapid, involuntary changes in mood or affect and can occur with neurological disorders, mood disorders, brain injury, or certain medications. The term can also apply to laboratory measurements or biological processes that fluctuate over time.