trusty

Meriting trust; trustworthy. synonym: reliable.

A prison inmate granted certain privileges and benefits or accorded certain duties by virtue of having been recognized as trustworthy.

A trusted person.

True; trustworthy; faithful; that may be implicitly confided in: applied to persons: as, a trusty servant.

Not liable to fail; that may be relied upon, as in an emergency; strong; firm: applied to things: as, a trusty sword.

Trusting; trustful.

Involving trust and responsibility.

A trusty person; specifically, a well-behaved and trustworthy convict to whom special privileges are granted.

Admitting of being safely trusted; justly deserving confidence; fit to be confided in; trustworthy; reliable.

Hence, not liable to fail; strong; firm.