"Black Dog" is a song by British singer and poet Arlo Parks from her debut studio album Collapsed in Sunbeams (2021). Named after Winston Churchill's term for depression, the song focuses on mental health, especially during the COVID-19 lockdowns. "Black Dog" was Parks' first song to make mainstream radio airplay in the UK, landing on the A List on the BBC Radio 1 Playlist in July 2020. Critics at NME ranked "Black Dog" as the 4th best song of 2020.