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Brian HIn the mid 1890's when Cap Anson -- then known as "Pop" because of his realtively advanced age -- left the Chicago team now known as the Cubs the team was briefly known as the "Orphans" -- since they had lost their "Pop."
.... BTW Anson left for the Giants after some arguments with Spaulding etc.
There are some other fun origin stories that escape my recollection at present for the Pirates etc.