Answer: mmd

AnswerCrossword Clue
MMD

Year around the middle of our millennium

MMD

L squared

MMD

C x XXV

MMD
CCL x X
MMD
End of the 25th century
MMD2500, in old Rome
MMDRoman 2,500
MMDSci-fi year
MMDRoman square?
MMDMid-millennium year
MMDTwice MCCL