lengþ

Lengþ is a theoretical unit used in linguistic typology and worldbuilding to describe the perceived tempo of speech in a given language. It is conceived to reflect how long segments appear to listeners, integrating vowel length, consonant closure, syllable structure, and natural speech rate. The term is not part of the formal inventory of mainstream phonology, but is encountered in speculative linguistics and fiction.

Etymology: The term blends the generic word length with the old-style thorn spelling to evoke historical Germanic language orthographies. It was popularized in informal discussions and some conworld writings, but has no standardized etymology in scholarly use.

Definition and measurement: Lengþ is a dimensionless index describing relative speech tempo. It is operationalized by comparing a language's mean syllable rate (or mean segment duration) to a reference language under controlled conditions; higher lengþ implies slower perceived tempo, lower lengþ implies faster tempo. It is sensitive to speech rate, style, and material, and is not tied to a single phonetic parameter.

Applications and limitations: Used as a heuristic in cross-language comparisons, rhythm typology, and speech synthesis design, as well as in worldbuilding to establish a language's "feel." Critics note that lengþ conflates many factors and lacks a universal standard, making cross-language comparisons context-dependent.

See also: speech rate, rhythm, tempo, prosody, phonology.