Musing is a period of deep thought, meditation or reflection.(noun)
When you are sitting in your house staring out the window and thinking deeply about your life, this is an example of musing.
The definition of musing is something related to being in deep thought.(adjective)
A facial expression that shows you have thought deeply about something is an example of a musing expression.
See musing in Webster's New World College Dictionary
See musing in American Heritage Dictionary 4
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