光明正大

guāngmíngzhèngdà
  1. (of a person) honorable; not devious
  2. (of a behavior) fair and aboveboard; without tricks; openly
  3. (of a situation) out in the open

CEDICT

high-principled; open and aboveboard; just and honorable; frank and righteous; without artifice; fair and square

Wiktionary

胸怀坦白，言行正派。《朱子语类．卷七三．易．鼎》：「圣人所说底话，光明正大，须是先理会个光明正大底纲领条目。」《西游记．第三七回》：「我本是个光明正大之僧，奉东土大唐旨意，上西天拜佛求经者。」也作「正大光明。」

重編國語辭典

胸怀坦白，言行正派

維基詞典

Entry Composition

1 光明 guāngmíng
  1. light
  2. radiance
  3. (fig.) bright (prospects etc)
  4. openhearted
2 正大 zhèngdà
  1. (of behaviour, actions, etc.) proper; appropriate; legitimate; reasonable; above board; upright; honest
  2. proper; appropriate; legitimate; reasonable; above board; upright; honest

Related entries

明处 míngchù
  1. clear place
  2. out in the open