Meditation and clear thought are how people arrive at the truth.
The Prophet :saws: would go to cave Hira on the Mountain of light for the sake of meditation without distraction - and this is where he first encountered Gabriel :as: as an open bringer of instruction and received the first Quranic revelation.
Meditation does not mean having a blank mind though - since the mind is never blank. It is basically steering clear of banal thoughts and allowing what is most important to take priority.
Muhammad 47:24
أَفَلَا يَتَدَبَّرُونَ ٱلْقُرْءَانَ أَمْ عَلَىٰ قُلُوبٍ أَقْفَالُهَآ
English - Sahih International
Then do they not reflect upon the Qur'an, or are there locks upon [their] hearts?
English - Yusuf Ali
Do they not then earnestly seek to understand the Qur'an, or are their hearts locked up by them?
English - Pickthall
Will they then not meditate on the Qur'an, or are there locks on the hearts?
Al-Kahf 18:16
وَإِذِ ٱعْتَزَلْتُمُوهُمْ وَمَا يَعْبُدُونَ إِلَّا ٱللَّهَ فَأْوُۥٓا۟ إِلَى ٱلْكَهْفِ يَنشُرْ لَكُمْ رَبُّكُم مِّن رَّحْمَتِهِۦ وَيُهَيِّئْ لَكُم مِّنْ أَمْرِكُم مِّرْفَقًا
English - Yusuf Ali
"When ye turn away from them and the things they worship other than Allah, betake yourselves to the Cave: Your Lord will shower His mercies on you and disposes of your affair towards comfort and ease."
Yatadabbar means ponder.
Daabir means roots.
Yudabbir means arrange.
Adbar means to turn one's back (in this context voluntary seclusion)
All of them are related.
See also:
https://www.muftisays.com/blog/Seifeddine-M/3813_05-01-2015/the-meaning-of-attadabbur.html
