D defs.my
Entry 1 sense Webster, 1913

Millimeter

/mĭl'-əm-ētˌ-ẽr/ · Mil·li·me·ter · IPA /ˈmɪləˌmitɚ/
01 n. A lineal measure in the metric system, containing the thousandth part of a meter; equal to .03937 of an inch. See 3d Meter.
  1. 1.
    A lineal measure in the metric system, containing the thousandth part of a meter; equal to .03937 of an inch. See 3d Meter. See: Meter