Rahukaalam

In Hindu astrology, Rāhukāla (Sanskrit: राहुकाल, lit. 'period of Rahu') or Rahukālam (Sanskrit: राहुकालम्, romanized: Rāhukālaṃ) is an inauspicious period of the day, not considered favourable to start any good deed. The Rāhukāla spans for approximately 90 minutes every day between sunrise and sunset. This inauspicious period is strictly avoided while calculating muhurtas. However, routine tasks that have already been started are regarded to be permissible to continue as usual during this period. From Wikipedia