Ghayn
The voiced velar fricative — like a French r.
Sound
Ghayn is /ɣ/, a voiced velar (or uvular) fricative. The most useful English-speaker reference is the Parisian French r — the throaty r in rouge or Paris, not the rolled Spanish or Italian one. Another mental model: gargling water but with the voice on. The constriction is at or near the soft palate, and the airflow rasps over it.
Ghayn is the voiced counterpart of khaa (خ). Khaa is the same sound minus voicing — like clearing your throat. Ghayn adds vocal-cord vibration. Many learners produce one when they meant the other; the test is to put your fingers on your throat and feel for buzzing.
Be careful not to overshoot into ʿayn (ع), which is much further back in the throat (pharyngeal, not velar) and has a different quality entirely. Ghayn raspy and palate-ish; ʿayn constricted and deep.
Forms
Connecting behavior
Ghayn connects on both sides.
Easy to confuse with
ʿAyn (ع). Same skeleton in all four positions. The single dot above is ghayn; no dot is ʿayn. The two letters are also adjacent in the alphabet and traditionally taught together.
Examples in common words
A note on handwriting
Same shape family as ʿayn. The dot above is critical and is what readers look for first; in handwriting where the body of the letter has been simplified or rushed, the presence or absence of the dot is often the only thing keeping the two letters distinct.