Meaning
A ring or coil of the tress; the looped curl as a snare.
Literally: ring of the curl
How Iqbal uses it
Each coil of the beloved's hair is a ring or noose; the lover is bound in the halqa of the zulf as in a chain, a fixed conceit of willing captivity.
See it in the verse
Halqa-e-Zulf in Iqbal’s couplets
Khudi mein doob ja ghafil, ye sirr-e-zindagani hai
Nikal kar halqa-e-shaam-o-sahar se javedan ho ja
Nikal kar halqa-e-shaam-o-sahar se javedan ho ja
Dive into your selfhood, O heedless one — this is the secret of life. Step out of the ring of evening and morning, and become everlasting.
Selfhood · Self-Knowledge · Awakening
Nazar nahin to mere halqa-e-sukhan mein na baith
Ki nukta-ha-e-khudi hain misal-e-tegh-e-asil
Ki nukta-ha-e-khudi hain misal-e-tegh-e-asil
If you have no vision, do not sit in my circle of speech — for the subtleties of selfhood are like a sword of true steel.
Selfhood · Self-Knowledge · Courage