infixation

Infixation is a morphological process in which a language inserts a bound morpheme — an infix — into the interior of a word stem, splitting the stem into two parts that bracket the inserted element. Three parameters carve the construct: (1) the inserted material is a bound morpheme, not an independent word — this is what separates infixation from tmesis, which inserts a grammatically independent word into the same interior position; (2) the insertion occurs at a fixed morphophonological position within the stem (a specific boundary or segment), so the process is a rule of the grammar rather than a free choice of the speaker; (3) the host stem retains its lexical identity, and the infixed form remains analyzable as a variant of that stem. Paradigmatic cases: Tagalog actor-focus infix -um- (kain 'to eat' → k-um-in 'to eat'), and the frequently cited but disputed English -ab- (ab-sent, ab-sole). Infixation persists two ways: as a productive rule — speakers of a language coin new infixed forms on the fly, and the rule survives as long as it is applied — and as a stable category of description — grammars, morphology textbooks, and formal rule specifications continue to state where the infix attaches and what it marks. [formal: infixatio | substrate: mind | horizon: generations | explicit: yes | epoch: 0.01]