sis
noun
[ sɪs ]
• a person's sister (often used as a form of address).
• "where are you going, sis?"
Origin:
late 16th century: abbreviation.
sis
exclamation
• used to express disappointment, disgust, or contempt.
• "sis—the floor is dirty!"
Origin:
from Afrikaans sies .
SIS
abbreviation
• (in the UK) Secret Intelligence Service.
SI
abbreviation
• the international system of units of measurement.
Origin:
from French Système International .
