Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
morning [ˈmɔːnɪŋ] n у́тро#; (between midnight and 3 a.m.) ночь f
cpd (paper, sun, walk) у́тренний#
in the morning у́тром
3 o'clock in the morning 3 часа́ но́чи
7 o'clock in the morning 7 часо́в утра́
this morning сего́дня у́тром
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.