Darling or beloved
Darlah is a modern variation of the English word 'darling', used as a term of endearment. It likely evolved as a more formal-sounding name by adding the 'ah' suffix, similar to names like Darla or Marla. It conveys a sense of being cherished and loved.
Less common today
Darlah isn't in the latest US Top 1000. It last peaked at #9,829 in 2012.
US births per 5-year period, 1990βpresent (SSA data).