pilgrimage (to Makkah)
Masculine verbal noun (maṣdar). Related: حَاجٌّ (pilgrim, pl: حُجَّاجٌ), مَحَجَّةٌ (clear path). There is an entire surah called Al-Ḥajj (22).
Hajj is the fifth pillar of Islam, required once in a lifetime for those who are physically and financially able. Over 2 million Muslims perform it annually.