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definitions

hard-and-fast

[hahrd-n-fast, -fahst]
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SEE MORE SYNONYMS FOR hard-and-fast ON THESAURUS.COM

adjective

strongly binding; not to be set aside or violated: hard-and-fast rules.

Origin of hard-and-fast

First recorded in 1865–70
Related formshard-and-fast·ness, noun

Synonyms for hard-and-fast

SEE MORE SYNONYMS FOR hard-and-fast ON THESAURUS.COM
fixed, precise, inflexible, inviolable, rigorous, unambiguous.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for hard and fast

uncompromising, intractable, stringent, steadfast, resolute, strict, unyielding, rigid, rigorous, obstinate, adamant, immutable, immovable, entrenched, located, solid, situate, stiff, placed, stable
British Dictionary definitions for hard and fast

hard and fast

adjective

(hard-and-fast when prenominal) (esp of rules) invariable or strict
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Idioms and Phrases with hard and fast

hard and fast

Defined, fixed, invariable, as in We have hard and fast rules for this procedure. This term originally was applied to a vessel that has come out of water, either by running aground or being put in dry dock, and is therefore unable to move. By the mid-1800s it was being used figuratively.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.