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truth; reality
sincerity; honesty; fidelity
content; substance
(good) result
「実」 has other readings with different meanings.
実は、私も同じことを考えていた。
Actually, I was thinking the same thing.
実を言うと、まだ決めていない。
To tell the truth, I haven't decided yet.
実を言うと、あまり好きではない。
To tell the truth, I don't like it much.