thought vs explanation

thought and explanation both are nouns.

Word	Noun	Adjective	Verb	Adverb
thought	Yes	No	No	No
explanation	Yes	No	No	No

As nouns, explanation is a hyponym of thought; that is, explanation is a word with a more specific, narrower meaning than thought:

thought (noun)	explanation (noun)
the process of using your mind to consider something carefully	thought that makes something comprehensible
the content of cognition; the main thing you are thinking about	a statement that makes something comprehensible by describing the relevant structure or operation or circumstances etc.
the organized beliefs of a period or group or individual	the act of explaining; making something plain or intelligible
a personal belief or judgment that is not founded on proof or certainty