What are some four letter words ending in i?

WIKI

Leaving out the Italian (rigatoni, vermicelli, etc.), and other foreign Words (tabi, pachisi, swami), and names/proper nouns (Bambi, Hopi), some of the more common include:

bikini

safari

fungi(there are many -us Words that pluralize to -i, e.g. cacti, syllabi, stimuli, etc.)

quasi

wasabi

alibi

rabbi

graffiti

yeti

confetti

origami

tsunami

chili

deli

lei

ennui

taxi

When you skip foreign Words, proper nouns, and plural forms, the list is pretty limited, indeed.