Agnipurana 360.1

360.1

agnir uvāca
āṅīṣadarthe 'bhivyāptau sīmārthe dhātuyogaje /
ā pragṛhyaḥ smṛtau vākye 'pyāstu syāt kopapīḍyoḥ //

Agni said:
"Āṅ" [is used] in the sense of "a little", in pervasive extent, in the sense of a boundary, and when joined to a verbal root;
"ā", pragṛhya, is in recollection; and in a sentence; "ā" is also in anger and affliction.