Ambiguous keyboard

A text entry method in which multiple letters are mapped to each physical key, requiring disambiguation algorithms (typically dictionary-based) to determine the intended word from the sequence of key presses. Originally popularized by T9 predictive text on mobile phone numeric keypads, ambiguous keyboards reduce the number of physical keys needed — valuable for users with motor impairments who can reliably target only a small number of keys. Combined with word prediction, ambiguous keyboards can achieve entry rates several times faster than character-by-character selection while requiring minimal physical movement.