Reconstruction:Proto-Celtic/en

Etymology
From. Matasović reconstructs *eni for the whole preposition, but since the preposition triggers a nasal mutation/eclipsis instead of a lenition in its descendants, a closed syllable may be reconstructed instead. However, the attested closed syllable could be explained by the theory of the early apocope of final /i/ in unstressed words, usually used to explain the rise of the absolute and conjunct inflection in Old Irish (by treating conjunct forms in the unstressed category).

Preposition

 * 1) in