desirous of 'making water' or urinating ...1654 obs.
from Latin micturientem, pres. pple. of micturire to desire to urinate,
desiderative verb from mict-, minct-, mingere to make water
(desiderative - denotes a verb formed from another and expressing a desire to do the act by the root verb)
FIRST DOCUMENTED USE
1654 - See Example below
"...which by the often drawing in of his breath, twisting his legs, and more ill-favour'd faces than ordinary, gave Sancho to perceive his condition very micturient, and cacaturient."
(cacaturient, from Latin cacaturio I feel the need to defecate)
From: Pleasant Notes upon Don Quixot
By: Edmund Gayton, 1654
• A New English Dictionary on Historical Principles,
James Murray, 1887-1933