'rigidify' originates from English, formed by combining the adjective 'rigid' and the verb-forming suffix '-ify' (from Latin '-ficare'), where 'rigid' meant 'stiff' and '-ify' meant 'to make'.

'rigid' originates from Latin 'rigidus' meaning 'stiff', entered English via Old French/Medieval Latin; the Modern English 'rigid' combined with the suffix '-ify' produced 'rigidify' in later English.

Initially, the root meant 'stiff' (describing state); over time the derived verb came to mean 'to make or become stiff', i.e., 'to cause stiffness' or 'to render inflexible'.