Rigid

a.	1.	Firm; stiff; unyielding; not pliant; not flexible. Upright beams innumerable Of rigid spears. - Milton.
	2.	Hence, not lax or indulgent; severe; inflexible; strict; as, a rigid father or master; rigid discipline; rigid criticism; a rigid sentence. The more rigid order of principles in religion and government. - Hawthorne.

Adj.	1.	rigid - incapable of or resistant to bending; "a rigid strip of metal"; "a table made of rigid plastic"; "a palace guardsman stiff as a poker" Synonyms: stiff
	2.	rigid - incapable of compromise or flexibility Synonyms: strict
	3.	rigid - incapable of adapting or changing to meet circumstances; "a rigid disciplinarian"; "an inflexible law"; "an unbending will to dominate" Synonyms: unbending, inflexible
	4.	rigid - fixed and unmoving; "with eyes set in a fixed glassy stare"; "his bearded face already has a set hollow look"- Connor Cruise O'Brien; "a face rigid with pain" Synonyms: fixed, set
	5.	rigid - designating an airship or dirigible having a form maintained by a stiff unyielding frame or structure Antonyms: nonrigid - designating an airship having a shape maintained only by internal gas pressure and without a supporting structure

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