internal reconstruction


noun Historical Linguistics.

the hypothetical reconstruction of an earlier stage of a language or of some part of it, as its phonology, by deductions from irregularities in its present structure, as the reconstruction of a stage in English when certain instances of r were related to s in a systematic way by comparing the pair was:were to other pairs, as lose:forlorn.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019