= Uniqueness point
A word's <uniqueness point> is the earliest point in its spoken form at which the sounds heard so far distinguish it from all competing words in a specified vocabulary. It connects a <cohort model> of <spoken word recognition> to the changing size of the <lexical cohort>.<Processing interactions and lexical access during word recognition in continuous speech by William D. Marslen-Wilson and Alan Welsh>[Cohort account of continuous spoken-word recognition]{ref}
For an invented vocabulary, let three word forms be the <phoneme> sequences $pat a$, $pan a$ and $pit a$, with spaces ignored and each symbol representing one <phoneme>. The third word becomes unique after $pi$, while the first two remain ambiguous after $pa$ and diverge at the following consonant. Uniqueness can therefore precede the end of a word.
This is a property of the chosen vocabulary and transcription, not a universal timestamp attached to a spelling. Adding another word beginning $pi$ changes the example. A word that is a complete prefix of another may require an end-of-word cue. Measured <reaction time> also includes perceptual, decision and motor processes, so it need not equal the lexical uniqueness time.
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