O.E. gadrian, gædrian "to gather, collect, store up," related to gæd "fellowship," and god "good," from P.Gmc. *gadurojan "bring together, unite" (cf. M.L.G. gadderen, O.Fris. gaderia). Change of spelling from -d- to -th- is 1500s, reflecting earlier change in pronunciation. Related: Gathered; gathering.