i guess there are more 'technical' words but i guess it is very 'teenager'-y to use a fancier/bigger word than you need to, to sound smarter, or learning vocabulary in english class, everyone kept saying 'exacerbate' when we learned it just b/c we were immature and found it amusing that it sounded like masturbate
but yeah i only ever hear 'capsicum' used when it's explaining why peppers are spicy (altho even that is tech another word and capsicum is just an overall pepper/the floral name like scientific, i wonder how many ppl say Helianthus instead of sunflower tho i'd find it awkward to hear even if i went into a floral shop)