chiliaëdron

In a Man who ſpeaks of a Chiliaëdron, or a Body of a thouſand ſides, the Idea of the Figure may be very confuſed, though that of the Number be very diſtinct; ſo that he being able to diſcourſe, and demonſtrate concerning that part of his complex Idea, which depends upon the Number of a Thouſand, he is apt to think, he has a diſtinct Idea of a Chiliaëdron; though it be plain, he has no preciſe Idea of its Figure, ſo as to diſtinguiſh it, by that, from one that has but 999 ſides.