The words damming sound the same but have different meanings and spellings. Why do damming sound the same even though they are completely different words?
The answer is simple: damming are homophones of the English language.
That condemns or exposes to condemnation or damnation: as, <em>damning</em> proof; <em>damning</em> criticism.
That damns; damnable.
Present participle of <xref>damn</xref>.
Property which <xref>damns</xref>.
Definitions from The Century Dictionary., from the GNU version of the Collaborative International Dictionary of English., from Wiktionary, Creative Commons Attribution/Share-Alike License. and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.