Rival, laborious, or eager
Emiliah is a modern elaboration of the name Emilia, which stems from the Roman family name Aemilius. It carries the dual connotations of being a 'rival' in terms of excellence and being 'industrious' or 'hardworking'. This specific spelling adds a soft, airy ending to the classic root.
Less common today
Emiliah isn't in the latest US Top 1000. It last peaked at #8,532 in 2019.
US births per 5-year period, 1990βpresent (SSA data).