As a writer, I am fascinated with the way words play in the mouth, their timbre and color, the way they change the air and mood of a room quickly, just by being spoken. Some of it is the meaning behind them, some of it is just the pure sound.
Take words with the letter K, especially in combination with L or short I, or hallelujah when you put them all together, tickle, pickle, oo da ickle snookums, even nickel. Comedians know this to be true. Minus slapstick, the next thing to make people laugh is language, especially words with K.
Alas, there were copyright restrictions on an astounding dialogue on exactly this topic between George Burns and Walter Matthau that prevented my sharing it with you via video. Instead I will recommend one of the funniest comedies ever to hit the screen. Neil Simon's The Sunshine Boys, 1975.
It's worth renting, but I would go so far as to purchase for my permanent collection. In fact, I'm off to do so! It really tickles the funnybone. (so I'm not a comedian, but I can try!)