transmittance
Meaning
the ratio of the light or other radiation passing through a substance to the light or radiation falling upon it.
the degree to which a medium allows something, such as electromagnetic radiation or sound, to pass through it.
Structure
Usage
the transmittance of the optical filter was measured at 95% for visible light.
low atmospheric transmittance in the infrared spectrum can affect satellite communications.
the glass's high ultraviolet transmittance makes it unsuitable for protecting sensitive artifacts.
Etymology
The word "transmittance" is a modern scientific term built from classical components. Its core is the Latin verb mittere, meaning "to send," which is embedded in the root "mitt." This is prefixed with "trans-," meaning "across," to form the concept of sending something across a space or through a medium. The suffix "-ance," deriving from Latin -antia, is then added to convert the action into a noun denoting the measurable state or quality of allowing passage. Thus, the literal progression from "sending across" to the abstract scientific concept of "the fraction of radiation transmitted" is a clear example of how precise technical vocabulary is constructed from ancient roots.
Analysis
trans: from latin, a prefix meaning "across," "beyond," or "through." it indicates movement or conveyance from one place or state to another. mitt: from latin mittere, meaning "to send." it is a bound root form appearing in words related to sending or letting go. ance: from latin -antia, a suffix forming nouns that denote a state, quality, or condition.