noun pl. etymologies -·gies

1. the origin and development of a word, affix, phrase, etc.; the tracing of a word or other form back as far as possible in its own language and to its source in contemporary or earlier languages: in this dictionary etymologies are given in doubled brackets preceding the senses to which they apply
2. the branch of linguistics dealing with word origin and development

Etymology: ME & OFr ethimologie < L etymologia < Gr: see etymon & -logy