In astrophysics, spaghettification is described as the “vertical stretching and horizontal compression of objects into long thin shapes” which is a nice way of saying “stretched to unholy proportions from head to toe”. This is caused by tidal forces which is a secondary effect of gravity. Gravitational force exerted by one body on another isn’t constant across it, the nearest side is attracted more strongly that the farthest side. Tidal waves dude.
Say you’re an astronaut who passes by a black hole’s event horizon (the point of no return and unequivocal doom), you would experience being stretched like spaghetti. Your body would be pulled all noodle like and for a verrrryyyy brief moment you’d actually feel great cause who doesn’t like a good stretch? That is until the gravitational force acting on your body is greater than the molecular force holding together your flesh and your spine snaps in two (probably at the base), and then those two continuously stretching body parts are stretched until THEY snap in two and so forth UNTIL THERE IS NOTHING LEFT OF YOUR EXISTENCE.
If your very dear friend George Clooney where watching you, he’d never see you reach the black hole. As you fall towards it, gravity would cause any light coming from you to be continuously redshifted which just means the light reflected off of you would increase in wavelength and shift into the red end of the spectrum (hence, redshift). Your image would look redder and redder also becoming dimmer and dimmer.
The scary part? The larger the black hole, the weaker the tidal forces near its event horizon so if you were traveling near a supermassive black hole you could cross the event horizon without ever noticing you’re being stretched into spaghetti.