meditation
Many people enter a meditative state without even realising it.
A soft, quiet, meditative calm had settled down upon his stern features.
It's a quietly meditative film, with stunning photography.

SMART Vocabulary: related words and phrases

Thinking and contemplating
a brown studyidiom
agonize
agonize over/about something
beard-stroking
bethink
harbour
heart-searching
hit on/upon something
I/we'll (have to) seeidiom
in the cold light of dayidiom
introspect
navel
reckon
reflection
reweigh
rumination
run through someone's mind/headidiom
scratch your headidiom
self-contemplation
weigh

You can also find related words, phrases, and synonyms in the topics:

Meditation, religious chanting & spiritual states
Deep in thought