Gen 15, 6 And he aman [believed in, was firm in] YHWH; and he counted it to him for righteousness. 

Aman to support, confirm, be faithful

a) (Qal)

      1) to support, confirm, be faithful, uphold, nourish

           a) foster-father (subst.)

           b) foster-mother, nurse [naomi, who called herself mara bitter, the nurse to Obed]

           c) pillars, supporters of the door [Boaz, the left pillar]

b) (Niphal)

      1) to be established, be faithful, be carried, make firm

          a) to be carried by a nurse

          b) made firm, sure, lasting

          c) confirmed, established, sure

          d) verified, confirmed

          e) reliable, faithful, trusty

c) (Hiphil)

     1) to stand firm, to trust, to be certain, to believe in

          a) stand firm

          b) trust, believe