subnormal

Subnormal is an adjective describing something that is below what is considered normal in degree, amount, or function. The exact meaning depends on context, as “normal” varies across fields and situations. In general, the term is used to indicate a shortfall relative to an established standard or expectation.

In computing and digital arithmetic, subnormal numbers (also called denormal numbers) are floating-point values with magnitudes smaller than the smallest normal representable number. In IEEE 754 formats, they have the exponent field set to its minimum value and do not use the implicit leading digit 1 in the significand. Subnormal numbers enable gradual underflow toward zero and allow representation of very small values, but they come with reduced precision and can slow arithmetic on some hardware.

In medical and clinical usage, subnormal has been used to denote measurements that fall below the normal reference range, such as subnormal temperature or subnormal respiratory rate. Historically it has also appeared in descriptions of people with intellectual disability; this usage is now considered outdated and stigmatizing. Modern language tends to use terms like intellectual disability or below-average intellectual functioning, and emphasizes respectful, person-centered terminology.

Outside these domains, subnormal can function as a generic descriptor for performance, responses, or outputs that are below the expected standard. Across contexts, the term is increasingly replaced by more precise or neutral language aligned with current norms and professional guidelines.