indispensable
in.dis.pens.able \-'pen(t)-s*-b*l\ \-ble-\ aj 1: not subject to being set aside or neglected {an ~ obligation} 2: absolutely necessary : ESSENTIAL {an ~ worker} - indispensable n
in.dis.pens.able \-'pen(t)-s*-b*l\ \-ble-\ aj 1: not subject to being set aside or neglected {an ~ obligation} 2: absolutely necessary : ESSENTIAL {an ~ worker} - indispensable n