rock-solid

adjective

rock-sol·​id ˈräk-ˈsä-ləd 

variants or rock solid

: completely or perfectly solid (as because of great strength or dependability)

supported by a rock-solid foundation

She has a rock-solid reputation.

Their relationship was rock solid.

… she moved in an artificial world without ever losing her rock-solid integrity.

—Walter Clemons

He is right to imply that the political structure is a little shaky—it was a myth that it was ever rock solid.

—Xan Smiley

Examples of rock-solid in a Sentence

Recent Examples on the Web

Then again, so do Liebling’s portraits of aldermen who block the construction of new housing, presumably afraid to soil their own rock-solid constituencies. —Christopher Borrelli, Chicago Tribune, 24 June 2025

The United States’ allies will do even more for collective defense in the future, backed by Washington’s rock-solid commitment to NATO. —Mark Rutte, Foreign Affairs, 20 June 2025

Ensure that the core product is rock-solid before scaling up with new features. —Expert Panel®, Forbes.com, 18 June 2025

Alexander Romanov has become a rock-solid top-four presence for the Islanders. —Harman Dayal, New York Times, 15 June 2025

Word History

First Known Use

1871, in the meaning defined above

Rhymes for rock-solid

• semisolid
• solid
• squalid
• stolid