Other forms: solidified, solidifying, solidifies
To solidify is to make or become firm. The wax solidifies, solidify support, solidifying position.
In physics it is freezing by another name — a liquid solidifies at its freezing point, and most substances contract doing so, though water famously expands. Figuratively it means making something settled: solidifying a lead. Note solid; and that the -ify ending makes verbs, as in simplify.
1verbsolidifyTo make or become firm.
“The melted wax solidified as it cooled in the mould.”
solidify is a hardening.
French solidifier comes from solide, from Latin solidus, firm. Solder, soldier and consolidate come from the same firmness.
French
solidifier
English, today
solidify
From French solidifier. by surface analysis, solid + -ify.
Etymology from Wiktionary, CC BY-SA