To depend on with full trust or confidence. You can rely on her to keep your secrets safe.
To be dependent on something or someone for support or help. The farmers rely on the weather for a good harvest.
To have or be based on something as a reason or foundation. His conclusion relies on several unverified assumptions.
To make use of or cite (something) as authority, evidence, or justification for an action or argument. Courts often rely on precedent when interpreting the law.