اِطْبَأَنَّ

i. q. اِطْمَأَنَّ; (S, K;) formed from the latter by substitution [of ب for م]. (S in article طمن.) So in the phrase اِطْبَأَنَّ قَلْبُهُ, meaning His heart became quiet, at rest, at ease, or tranquil. (TA.)