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Synonyms for Si (same or very similar meaning)

WordNet sense 1 (a tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and feldspar and granite and quartz and sand; used as a semiconductor in transistors):

WordNet sense 2 (a complete metric system of units of measurement for scientists; fundamental quantities are length (meter) and mass (kilogram) and time (second) and electric current (ampere) and temperature (kelvin) and amount of matter (mole) and luminous intensity (candela)):
Systeme International d'Unites, International System, International System of Units, SI system, Systeme International

WordNet sense 3 (the syllable naming the seventh (subtonic) note of any musical scale in solmization):
ti, te

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