Hugutio Pisanus Hugutio Pisanus, Derivationes, p19, p301, 21 Item a sto vel steti hec stera -e, pellicula in qua pueri in ventre involvuntur et morantur; unde Macer (Odo Magd. 101-02) ‘stere si subditur erba, desiccabit eam’; et inde stericus -a -um, ad steram pertinens vel in stera patiens et infirmatus, unde idem (Odo Magd. 13) ‘duritiam stericis solvit’; et hic et hec sterilis -e, infructuosus, infecundus, nichil aptus gignere, et comparatur, unde hec sterilitas; et per compositionem hec obstetrix -cis, idest femina que steram tractat, scilicet que recolligit puerum de ventre procedentem; vel derivatur ab obsto -as, unde obstetrix quasi obstatrix, quia obstat parturienti, et inde obstetrico -as, tale officium exercere.