SPFSPF /ˌes piː ˈef/ noun [singular, uncountable] 
(Sun Protection Factor) a number that shows you how much protection a special cream gives you from the sun: 
an SPF 25 cream
(Sun Protection Factor) a number that shows you how much protection a special cream gives you from the sun: an SPF 25 cream- interference
- interferon
- intergalactic
- intergenerational
- intergovernmental
- interim
- interior
- interior decorating
- interior decorator
- interior design
- interior designer
- interject
- interjection
- interlace
- interlaced
- Interlingua
- interlink
- interlock
- interlocutor
- interloper
- interlude
- intermarriage
- intermarry
- intermediary
- intermediate