Final answer:
Acrostic poems are phrases, rhymes, or poems in which the first letter of each word is a cue to retrieve another word which begins with the same letter. They are used to convey hidden messages or messages that are revealed when certain letters are put together vertically.
Step-by-step explanation:
Phrases, rhymes, or poems in which the first letter of each word is a cue to retrieve another word which begins with the same letter are called Acrostic poems. An Acrostic poem is a type of poem where certain letters in each line spell out a word or phrase when read vertically. For example, in the phrase 'Mother', the vertical column formed by the first letter of each line spells out the word 'MOTHER'.
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