Quidam | Webster's Dictionary of the English Language

quidam
quīdam, quaedam, quoddam, and subst. quiddam, pron. indef. , a certain , a certain one , somebod...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
quidam
quīdam quaedam, quoddam, and (as subst.) quiddam, pronindef.—Sing., a certain, a certain one, someb...

An Elementary Latin Dictionary