Streeter developmental horizon(s)
Pronunciation: stre'ter de-vel'op-men'tal ho-ri'zon[z]
A term borrowed from geology and archeology by Streeter to define 23 developmental stages in young human embryos, from fertilization through the first 2 months; each horizon spanned 2–3 days and emphasized specific anatomic characteristics, to avoid discrepancies in the determination of age and body dimensions.
Search Stedman's Medical Dictionary
Examples: glitazone, GI cocktail, etc.