in-concessus

a, um, adj.
I. not allowed, impossible (not ante-Aug. and rare): hymenaei, Verg. A. 1, 651; cf. ignes, Ov. M. 10, 153: spes, id. ib. 9, 638: cum totum exprimere paene sit homini inconcessum, Quint. 10, 2, 26.
Lewis & Short
A Latin Dictionary, 1879
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