A spelling variant of Emily, from the Latin Aemilia name family meaning "rival" or "eager."
Emilly is a distinctive variant spelling of Emily, one of the most enduringly popular feminine names in the English-speaking world. The name traces its lineage to the Latin family name Aemilius, from the Roman gens Aemilia — a patrician clan whose name likely derives from the Latin aemulus, meaning 'rival,' 'striving to equal,' or 'industrious.' From Rome it passed into medieval Europe via the feminine form Aemilia, and by the time of Chaucer's fourteenth-century Canterbury Tales — where Emily appears as the beautiful object of two knights' devotion in 'The Knight's Tale' — it had become a recognizable English name.
The roll call of famous Emilys is extraordinary: Emily Brontë, whose Wuthering Heights remains one of the most passionate novels in the English language; Emily Dickinson, the reclusive American poet whose slant-rhymed meditations on death and immortality reshaped American literature; Emily Pankhurst, the suffragist who helped secure British women the right to vote. The name carries, through these bearers, an association with fierce interiority, intellectual independence, and quiet revolutionary force. The spelling Emilly — with its double 'l' — sets the bearer apart from the crowd of Emilys without departing from the name's familiar sound.
It is a small act of individuation, a typographic signature. Names with variant spellings often generate affectionate debate between bearers and spell-checkers, but they also create a sense of ownership: this is not simply Emily, but something slightly more particular, more personal, more one's own.