paleomnesia n. good memory for events of the far past.
icosian adj. of or relating to twenty.
hypermimia n. excessive gesticulating while talking.
from Mrs. Byrne's Dictionary of Unusual, Obscure, and Preposterous Words, by Josefia Heifetz Byrne.
(My edition is the 1990 paperback. A tip of the rainhat to those who can use all three of the above in a sentence.)