The affix ṇa to the name of a weapon indicates a game played with that weapon.,
The sutra literally translated means: 'that is the weapon in this, denoting play; the affix ण is added' i. e. to a word in the first case in construction, denoting the name of a weapon; ण is added to denote a play. Thus दण्डः प्रहरणमस्यां क्रीडायां = दाण्डा \a game played with sticks\. So मौष्टा \a game played with fists\.
Why do we say 'a weapon'? Observe माला भूषणमस्यां क्रीडायाम् 'the garland is an ornament in this play'. Here no affix is added to माला ॥ Why do we say 'in denoting a game'? Observe:- खड्गः प्रहरणमस्यां सेनायाम् 'the sword is the weapon in this army'. These words are as a rule in the feminine gender 4.1.4 and 4.1.15, the feminine being formed by आ ॥,