The story
- Proto-Italic*moltos
- Latinmultus
- Latinmultī
- Middle Englishmulti-
- Englishmulti-
- Latincultūra
- Middle Frenchculture
- Englishculture
- Englishmulticultural
- English todaymulticulturally
From multicultural + -ly.
Etymology from Wiktionary, CC BY-SA 4.0.