Lewis & Short

illăcrĭmābĭlis (inl-), e, adj. [in-lacrimabilis].

  1. I. Unwept, unlamented, ἄκλαυστος: sed omnes illacrimabiles Urgentur ignotique longa Nocte, Hor. C. 4, 9, 26 (cf. indefletus, Ov. M. 7, 611).
  2. II. That is not or cannot be moved by tears, pitiless, inexorable: Pluto, Hor. C. 2, 14, 6: urna, Aus. Epit. 36, 3.