The spelling of the word "most effecting" may seem confusing, but it is actually incorrect. The correct spelling is "most affecting". The word "affecting" is spelled with an "a" instead of an "e" because it comes from the verb "affect", meaning to have an impact on something or someone. The stress is on the second syllable, so it is pronounced [uh-fek-ting]. It is important to use correct spelling and pronunciation in order to effectively communicate your message.
The phrase "most effecting" is derived from the word "effect", which is a noun meaning the result or consequence of an action. The adjective "effective" is derived from this noun. "Most effecting" is the superlative form of "effective", indicating that it has the highest degree of effectiveness among multiple things or actions being compared.