To the affixes tara and tama (gha -- taraptamapau ghaḥ [[1.1.22]]) ordained to come after the word kim -- atiśāyane tamabiṣṭhanau [[5.3.55]], or after a word ending in e -- ghakālataneṣu kālanāmnaḥ [[6.3.17]], or after a finite verb -- tiṅaśca [[5.3.56]], dvivacanavibhajyopapade tarabīyasunau [[5.3.57]], or after an indeclinable, is added the affix ām , but not if the excess belongs to a substance (and not to an action or quality),
The घ or तरप् and तमप् affixes are employed for comparison (प्रकर्ष 'excess') of adjectives and adverbs This rule applies to adverbs and not to adjectives : i. e. when an adverb qualifies a verb or another adjective, but not when an adjective qualifies a noun. The द्रव्य denoting word by itself has no 'excess' &c, it is the adjective which qualises such substance that is capable of excess or comparison. The prohibition in अद्रव्यप्रकर्ष therefore really relates to the quality of a substance; i. e. to adjectives. द्रव्यस्याव्यपदेश्यस्य न विना भेद हेतुना । प्रकर्षोविद्यते नापि शब्दस्योपेति वाच्यताम् ॥
Thus किंतराम् or किन्तमाम् \how excessively\, पूर्वाह्णेतराम् or पूर्वाह्णेतमाम्, पचतितराम् or पचतितमाम् \he cooks surprisingly\, उच्चैस्तराम्, उच्चैस्तमाम् \more or most loftily or loudly\.
But when the excess belongs not to an action or attribute, but to a substance, the amu आम् is not added. As उच्चैस्तमः तरुः \a most lofty tree\.,