The affix gha generally comes in the sense of an instrument or location after a root, when the word to be formed is a name and is in the masculine gender.,
The force of the word प्रायेण 'generally' is to show that this rule is not a universal rule. Thus दन्तच्छदः 'the lip'. छादि 'to cover' + घ 6.4.96 = छद lit. 'that by which the teeth are covered'; so also उरच्छद 'a breast plate'; घटः । These denote instruments.
So also in denoting 'location'. Thus आ + कृ + घ = आकरः 'a mine', so named because men work (akurvanti) in it, आलयः 'a house' that in which men settle down.
Why do we say 'in the masculine gender'? Observe प्रसाधनम् 'a comb'; (lit. that by which men decorate). Here the affix is lyut.
Why do we say 'when the complete word so formed is merely an appellative'? Observe प्रहरणो दण्डः 'the beating stick'.
The indicatory घ् is merely qualifying; for the application of sutra (VI. 4. 96.) by which after the causative छादि, when घ is added, the long आ is shortened.,