rely
Concise Oxford English Dictionary © 2008 Oxford University Press:
rely/rɪˈlʌɪ/
▶verb (relies, relying, relied) (rely on/upon)
- 1 trust fully; have faith in.
- 2 be dependent on.
– origin ME (orig. in the sense ‘gather together’, later ‘turn to’): from OFr. relier ‘bind together’, from L. religare, from re- (expressing intensive force) + ligare ‘bind’.
'rely' also found in these Oxford entries:

