katamá (as), (ā), (at), mfn. (superlative of 2. ka; declined as a pronom., [Gram. 236]), who or which of many? (e.g. katamena pathā yātās te, by which road have they gone?)
it is often a mere strengthened substitute for ka, the superlative affix imparting emphasis
hence it may occasionally be used for ‘who or which of two?’ (e.g. tayoḥ katamasmai, to which of these two?)
it may optionally be compounded with the word to which it refers (e.g. katamaḥ kaṭhaḥ, or katama-kaṭhaḥ, which Kaṭha out of many?)
when followed by ca and preceded yatama an indefinite expression is formed equivalent to ‘any whosoever’, ‘any whatsoever’, &c. (e.g. yatamad eva katamac ca vidyāt he may know anything whatsoever). In negative sentences with cana or with api = not even one, none at all (e.g. na katamaccanāhaḥ, not even on a single day, on no day at all)
in addition to the above uses is said to mean ‘best’, ‘excessively good-looking’ (cf. 3. ka), [RV.] &c.