1.Contractioncontraction of an (“at/on”) + dem (“the”, masculine/neuter dative singular) .mw-parser-output .object-usage-tag{font-style:italic}.mw-parser-output .deprecated{color:var(--wikt-palette-grey-lime-8,olivedrab)}[with adjective ending with -en and masculine or neuter noun]
"am Ende; am Rande; am Leben"
2.Contractioncontraction of auf (“on/at”) + dem (“the”, masculine/neuter dative singular) [with adjective ending with -en and masculine or neuter noun]
"am Berg; am Fest; am Schirm"
3.ParticlePrecedes the superlative in adverbial and predicate use.
"am schnellsten; am schwächsten; am wichtigsten; Er spielt am besten."
4.ParticleGerman Wikipedia has an article on:am-progressivWikipedia Used to form the progressive aspect of verbs, especially intransitive ones. [with gerund]