eight·i·eth 
(ātē-ĭth)
(ātē-ĭth)n.
1. The ordinal number matching the number 80 in a series.
2. One of 80 equal parts.
eighti·eth adv. & adj.
- psychobiologist
- psychobiology
- psychochemical
- psychodrama
- psychodramatic
- psychodramatist
- psychodynamic
- psychodynamically
- psychodynamics
- psychogenesis
- psychogenetic
- psychogenetically
- psychogenic
- psychogenically
- psychograph
- psychographic
- psychographics
- psychohistorian
- psychohistorical
- psychohistory
- psychoimmunologist
- psychoimmunology
- psychokinesis
- psychokinetic
- psychokinetically