To accompany or occur together with something else; to be concurrent or coexistent.
Directly from Latin concomitari (to accompany), formed from con- (with) + comitari (to attend or follow). This verb form is rare and archaic, appearing mainly in historical texts.
This is an incredibly rare verb that almost nobody uses anymore, but if you spot it in an old book, it simply means 'to go with' or 'to happen at the same time'—it's like the forgotten ancestor of our more common 'concomitant.'
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