Толковый словарь английского языка

[Word Family: noun: ↑reliability, ↑reliance; adjective: ↑reliable ≠ ↑unreliable, ↑reliant; verb: ↑rely; adverb: ↑reliably]

[Date: 1300-1400; Language: Old French; Origin: relier, from Latin religare 'to tie back']

rely on/upon somebody/something phrasal verb

1. to trust or depend on someone or something to do what you need or expect them to do ⇨ reliable, reliance:

I knew I could rely on David.

rely on somebody/something to do something

Many working women rely on relatives to help take care of their children.

rely on/upon somebody/something for

Many people now rely on the Internet for news.

2. to depend on something in order to continue to live or exist:

For its income, the company relies heavily on only a few contracts.

rely on/upon somebody/something for

They have to rely on the river for their water.