The phrase, 'Period of time' is a tautology, surely.
It can be, but there are other periods, so it may well be appropriate to specify in some instances, and it could be argued that it's a multiple-word noun of sorts, like "hot dog bun" or "lily of the valley". Anyway, we have a length of time and a stretch of time, so a period of time can snuggle up to those and hope not to be noticed.
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It can be, but there are other periods, so it may well be appropriate to specify in some instances, and it could be argued that it's a multiple-word noun of sorts, like "hot dog bun" or "lily of the valley". Anyway, we have a length of time and a stretch of time, so a period of time can snuggle up to those and hope not to be noticed.