INDEFECTIBLE Meaning of INDEFECTIBLE in English [in.de.fec.ti.ble] adj (1659) 1: not subject to failure or decay: lasting 2: free of faults: flawless -- in.de.fec.ti.bil.i.ty n -- in.de.fec.ti.bly adv Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012