Monostich

A monostich is a poem which consists of a single line.
Form.
A monostich has been described as 'a startling fragment that has its own integrity'
and 'if a monostich has an argument, it is necessarily more subtle.'
A monostich could be also titled; due to the brevity of the form, the title is invariably as important a part of the poem as the verse itself:
Some one line poems have 'the characteristics of not exceeding one line of a normal page, to be read as one unbroken line without forced pauses or the poetics of caesura', and others having ' a rhythm, (as with one-line haiku), dividing easily into three phrases'.
History.
Almost all examples of monostich in English are translated from other languages, namely Russian and French.
Modern monostich was started in Russia in 1894 when Valery Bryusov published the single line of pretty absurdist essence:
Perhaps the first to re-introduce one line poems was Guillaume Apollinaire with his "Chantre" (1914) in his collection "Alcools" (1913), mentioned by Leroy Breunig in 'Apollinaire and the monostich' followed by Bill Zavatsky with his 'Roy Rogers' article (1974) in which he made clear that one line poems are not at all foreign to Western poetic tradition. Also including therein some from Jerome Rothenberg's 'Technicians of the Sacred' (1969), all of which are referenced in William Higginson's 'Characteristics of monostichs'. Emmanuel Lochac published in 1920 'one-liners' under the title "Monostiches".
Dmitry Kuzmin pointed out in the first book-length study of one-line poetry (2016), Walt Whitman, included a monostich (with the very long line though) in a 1860 edition of his "Leaves of Grass", and then in 1893 and 1894 Edith Thomas, possibly in collaboration with an amateur author Samuel R. Elliott (1836—1909), anonymously published in "The Atlantic Monthly" several one-line poems intended as a joke. In the 1920s one-line poetry was rediscovered in the US by Yvor Winters, Edwin Ford Piper, Charles Reznikoff and others. Later, John Ashbery in '37 Haiku' demonstrated the Haiku in the monostich form.
Ian McBryde's 2005 book "Slivers" consists entirely of one line poems. Jan 2020 Alive In Coffin started a blog dedicated to one line poem.