VERB (2)

1. make solid or more solid; cause to solidify;

2. become solid;
- Example: "The metal solidified when it cooled"

The Collaborative International Dictionary of English v.0.48:

Solidify \So*lid"i*fy\, v. t. [imp. & p. p. Solidified; p. pr.
   & vb. n. Solidifying.] [Solid + -fy: cf. F. solidifier.]
   To make solid or compact.
   [1913 Webster]

         Every machine is a solidified mechanical theorem. --H.
                                                  Spencer.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Solidify \So*lid"i*fy\, v. i.
   To become solid; to harden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

solidify
    v 1: make solid or more solid; cause to solidify
    2: become solid; "The metal solidified when it cooled"

Moby Thesaurus II by Grady Ward, 1.0:

127 Moby Thesaurus words for "solidify":
   abbreviate, add, adhere, agglomerate, amalgamate, assimilate,
   blend, body forth, bunch, cake, candy, circumscribe, clasp, cleave,
   clinch, cling, cling to, clot, cluster, coagulate, coalesce,
   coarct, cohere, combine, come together, compact, compound,
   compress, comprise, concentrate, concrete, concretize, condense,
   congeal, congest, conglomerate, connect, consolidate, constrict,
   constringe, contract, cram, cramp, crowd, crystallize, curtail,
   decrease, densen, densify, draw, draw in, draw together, dry,
   embody, embrace, encompass, entify, flux, freeze, freeze to, fuse,
   gel, granulate, grasp, grow together, hang on, hang together,
   harden, hold, hold on, hold together, hug, hypostatize, incarnate,
   include, incorporate, indurate, inspissate, integrate, interblend,
   interfuse, jam, jell, join, knit, lend substance to, lump together,
   make one, mass, materialize, meld, melt into one, merge, mix,
   narrow, persist, press, pucker, pucker up, pull together, purse,
   put together, ram down, reduce, reembody, reify, roll into one,
   set, shade into, shorten, squeeze, stay, stay put, stick,
   stick together, strangle, strangulate, sublime, syncretize,
   syndicate, synthesize, take a set, take hold of, thicken, unify,
   unite, wrinkle