Shirabe
English jmdict
1
noun (common) (futsuumeishi) bottom of one's heart;depths of one's mind;innermost thoughts;real intentions
彼は心底は善人だ。
He is a good man at heart.
2
adverb (fukushi) only applies to しんそこ from the bottom of one's heart;wholeheartedly;truly;sincerely
君には心底失望したよ。
I'm very disappointed in you.
Other forms 真底 【しんそこ】 (rarely used kanji form)