Protect

Protect[s1,s2,…] sets the attribute Protected for the symbols si.

Protect[patt1,patt2,…] protects all symbols whose names textually match any of the arbitrary string patterns patti.

Protect[{spec1,spec2,…}] protects any symbols that are equal to or whose names match any of the speci.

Please visit the official Wolfram Language Reference for more details and examples on core symbols.