***Since life forms are not made by the hands of men, is it possible for aliens to really not be aliens but just species unknown to humans? New species in the canopy of the rainforests are found quite often.

Yes, very possible. But the main point with UFOs/aliens is that their alleged existence would prove superior intelligence above man. Science has no claim for ANYTHING superior to man, even dieties, which are not scientifically acknowledged in the first place.

***If lockness, bigfoot, yeti, etc were found, would they be considered aliens since they have not been identified in scientists' taxonomy***

Not really, the term alien implies "not from this world" , specifically, extraterrestrial.

My point is that a UFO (unidentified flying object)
is what anything is considered until it can positively identified. So any classified military project MUST be officially a "UFO" because the identity is secret and will remain unidentified.

Kind of a catch-22

To date, in my knowledge, there is no confirmed flying object officially listed as "extraterrestrial".

Were you in DC area or Southwest (Arizona, Nevada, New Mexico, etc)?