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thick; deep; heavy
kind; cordial; hospitable; warm; faithful
serious (of an illness)
abundant
彼は信仰が篤い人だ。
He's a deeply religious person.
地域の人々の信仰はとても篤かった。
The faith of the local people was very deep.
最近の若者は信心がそう篤くない。
Young people these days aren't that devout.