Eid al-Adha 
(
əl-ä
d
ə, -äd
hä)
n. The 10th day of Dhu'l-Hijjah in the Islamic calendar, celebrated as a holiday commemorating Abraham's willingness to sacrifice his son.
[Arabic 'Īd al-'Aḍḥā, Feast of the Sacrifice : 'īd, feast; see EID + al-, the + 'aḍḥā, sacrifice (from 'aḍḥā, to become visible, since the sacrifice is performed soon after the sun rises; see ḥw in the Appendix of Semitic roots).]