Acrostiche

Part of speech: noun

Definitions

1. A poem or verse in which the first letters of each line spell out a hidden word or phrase when read downward
2. A verse composition where the opening letter of every line forms a word, name, or message when taken in order
3. Wordplay in poetry in which the initial letters of successive lines combine to spell a concealed word or name

Etymology: The Greek compound behind this word pairs "akros", meaning "highest" or "outermost", with "stichos", a line of verse. The name describes the trick exactly: the first letters of successive lines, read down the page, spell out a word or message. The device is far older than its name. Several books of the Hebrew Bible use it, most famously Psalm 119, whose eight-line stanzas each begin with the next letter of the Hebrew alphabet. English took the word through French, which had borrowed it from the Latin "acrostichis". The same "stichos" root appears in "distich", a pair of lines of verse, and in "stichomythia", a dialogue in which speakers trade single lines.