It is a high of 108 degrees F (42 C) here in Spain today which has inspired me to address a couple confusing words when describing warm weather... hot (adjective) vs. heat (noun) Today is really hot! Wow there is a lot of heat outside! *"More hot" cannot be used, we must say "hotter": It is hotter here than there. sunny (adjective) vs. sun (noun) Make sure you put on sunscreen because it is really sunny outside. Because of the sun, it is important to apply sunscreen. humid (adjective) vs. humidity (noun) Although the temperature is lower, it feels hotter because of the humidity. The air is really thick because it is humid.