Of or pertaining to a proem or proemium.(adjective)
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Use "proemial" in a sentence
"The epick writers have found the proemial part of the poem such an addition to their undertaking, that they have almost unanimously adopted the first lines of Homer, and the reader needs only be informed of the subject, to know in what manner the poem will begin."
"It is established at present, that the proemial lines of a poem, in which the general subject is proposed, must be void of glitter and embellishment."