Isthmmi

Isthmmi is a term used in speculative geography and fiction to describe a cultural, linguistic, or archaeological complex imagined to have developed along a chain of isthmuses connecting landmasses. The name is derived from isthmus, highlighting the central geographic idea of narrow land corridors facilitating contact between regions.

In archaeology and anthropology, Isthmmi is sometimes used as a thought-experiment label for an Isthmmian Archaeological Complex. In this framework, material culture includes coastal settlements, drainage or canal features, and exchange networks linked by narrow landbridges that bracketed what would have been different ecological zones.

In linguistics, Isthmmi refers to a hypothetical language family used to illustrate contact phenomena among communities separated by isthmian corridors. Isthmmian languages are described as sharing core lexical roots through trade-linked borrowing, with features such as flexible word order and affixal morphology arising from areal diffusion.

Outside scholarly discourse, Isthmmi appears in speculative fiction and role-playing games as a setting, faction, or cultural umbrella. Authors and designers use Isthmmi to explore themes of connectivity, borderlands, and cultural syncretism along a network of isthmuses.