word-forming element used in forming nouns from Latin words ending in -atus, -atum (such as estate, primate, senate). Those that came to English via French often arrived with -at, but an -e was added after c. 1400 to indicate the long vowel. The suffix also can mark adjectives formed from Latin past participles in -atus, -ata (such as desolate, moderate, separate); again, they often were adopted in Middle English as -at, with an -e appended after c. 1400.
late 14c., "large, rounded vase used to preserve the ashes of the dead," from Latin urna "a jar, vessel of baked clay, water-jar; vessel for the ashes of the dead" (also used as a ballot box and for drawing lots), probably from earlier *urc-na, akin to urceus "pitcher, jug," and from the same source as Greek hyrke "earthen vessel." But another theory connects it to Latin urere "to burn" (compare bust (n.1)).
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Definitions of urceolate from WordNet
urn-shaped; large below and contracted toward the mouth;