音 (Kanji for sound)

Onyomi

A dude makes a loud sound, if he's standing ON top of the sun . It goes like AIEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE.

おと	sound ★★★★★

音楽(おんがく)	music! ★★★★★ 音 (sound) + 楽 (enjoy) = 音楽 (music!)
発音(はつおん)	pronunciation of a word ★★★★☆ 発 (launch) + 音 (sound) = 発音 (pronunciation of a word)
音読み(おんよみ)	The kanji pronunciation one uses in compound words. ★★★☆☆ 音 (sound) + 読 (read) = 音読み (The kanji pronunciation one uses in compound words.) yep.
擬音語(ぎおんご)	Onomatopoeia! ★☆☆☆☆ 1/2 KANA 擬 (sham) + 音 (sound) + 語 (language) = 擬音語 (Onomatopoeia!) Onomatopoeia!!!! Sound-effect words. in English, that means words like 'slap' 'smack' or 'splash.'