My favourite words are: "crisp," "fresh," and "boots," "goods," or any word of the same construction. Those words induce in me a kind of delighted wriggling. Close upon them, but not as strong, are "packet" and "luscious" (only if lovingly enunciated).
Conversely, there are words I despise. I hate the word "tits": oh, I hate it! I hate the word "notion," with reference to sewing items. I hate hate hate hate hate hate the word "panties." I hate it so much I actually feel soiled for having written it. And there are words I hate so much I won't let them cross my lips, or my keyboard. They must remain forever loathed but unarticulated.
My mother, an English professor, told me once that she has no words she feels particularly one way or the other about. Madness, in my opinion.
These days, because I have so many international friends, I am being exposed to words from all languages. You already know my feelings about "puñalada," but you do not know that I really dislike the Spanish word "nunca." In Latin, "nunc" means "now," but "nunca" means "never." This is totally illogical: Spanish is a romance language! So it galls me.
On the other hand, I love the German word "Notausgang." It just means "emergency exit," but it sounds so vital and concerning. Similarly, I love "besonders," which means "especially" or "particularly," because I think it sounds like an expression of surprise: "Besonders, John, we're late for dinner!" (admittedly, I knew and loved these two words before). I love the Russian for yes, which I've heard a lot lately. "Da" is so firm: yes, and that's it. And I love the Spanish for "clay in your hands": "barro in tus manos." Yum. I love the Serbian for "planet," "planeta," largely because the stress falls on the penultimate syllable and the t is clearly articulated, so the words sounds nice and tidy. And I love a Russian phrase I can't even remember - the phrase that means "to make love." It's filled with soft z's, and I love it not exactly because of the way it sounds, nor because of what it means (because logically its sound-to-meaning ratio should drive me nuts: it's rather long, and it seems an unnecessarily long phrase to mean, "make love"), but because it's long enough that you could say it as you run your hand from the base of someone's throat all the way down their body, and it would take up all the time - and also sound a little bit like the motion itself, with its soft swooshing. So I like a phrase I can't remember, and couldn't pronounce even if I could remember it, because of its abstract erotic similarity.
Language: it expresses so little in its meanings, but so much in its sounds. And it tastes so good.