Based on tineas, new words formed by adding one letter at the beginning or end:
a - aeinst b - entasia c - taenias d - banties e - basinet f - acetins g - cineast h - destain i - detains k - instead l - sainted m - stained n - etesian o - fainest p - easting r - eatings s - ingates t - ingesta u - seating v - teasing w - sheitan x - sthenia z - isatine