From Wiktionary, the free dictionary
Adverbial accusative of عَبَث (ʕabaṯ, “vain”).
عَبَثًا • (ʕabaṯan)
- for no purpose, in play, uselessly, for nothing, futilely
609–632 CE, Qur'an, 23:115:أَفَحَسِبْتُمْ أَنَّمَا خَلَقْنٰكُمْ عَبَثًا وَأَنَّكُمْ إِلَيْنَا لَا تُرْجَعُونَ- ʔafaḥasibtum ʔannamā ḵalaqnākum ʕabaṯan wa-ʔannakum ʔilaynā lā turjaʕūna
- Then did you think that We created you uselessly and that to Us you would not be returned?
- → Ottoman Turkish: عبثا (abesan)