昏定晨省

hūndìngchénxǐng
seeing to bed in the evening and visiting in the morning (ancient filial duty)

CEDICT

晚间服侍父母就寝，早晨向父母请安。语本《礼记．曲礼上》：「凡为人子之礼，冬温而夏凊，昏定而晨省。」指子女侍奉父母的日常礼节。《孤本元明杂剧．群仙朝圣．头折》：「孝者侍养双亲，昏定晨省，冬温夏凊，以报生身之恩。」《儿女英雄传．第三三回》：「为人子者，冬温夏清，昏定晨省，出入扶持，请席请衽，也有个一定的仪节。」也作「晨昏定省」。

重編國語辭典

指子女侍奉父母的日常礼节

維基詞典

Entry Composition

=1 昏 hūn
  1. muddle-headed
  2. twilight
  3. to faint
  4. to lose consciousness
=1 昏 hūn old variant of 昏 hūn
2 定 dìng
  1. to fix; to set; to make definite
  2. to subscribe to (a newspaper etc); to book (tickets etc); to order (goods etc)
  3. to congeal; to coagulate
  4. (literary) definitely
3 晨 chén
  1. morning
  2. dawn
  3. daybreak
4 省 xǐng
  1. (bound form) to scrutinize
  2. (bound form) to reflect (on one's conduct)
  3. (bound form) to come to realize
  4. (bound form) to pay a visit (to one's parents or elders)