SI
| Pronunciation (US): |  |
Dictionary entry overview: What does Si mean?
• SI (noun)
The noun SI has 3 senses:
1. 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)
2. 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
3. the syllable naming the seventh (subtonic) note of any musical scale in solmization
Familiarity information: SI used as a noun is uncommon.
Dictionary entry details
• SI (noun)
Meaning:
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)
Classified under:
Nouns denoting quantities and units of measure
Synonyms:
Systeme International d'Unites; Systeme International; SI system; SI; International System of Units; International System
Context example:
Today the United States is the only country in the world not totally committed to the Systeme International d'Unites
Hypernyms ("SI" is a kind of...):
metric system (a decimal system of weights and measures based on the meter and the kilogram and the second)
Meaning:
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
Classified under:
Nouns denoting substances
Synonyms:
atomic number 14; silicon; Si
Hypernyms ("Si" is a kind of...):
chemical element; element (any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter)
semiconducting material; semiconductor (a substance as germanium or silicon whose electrical conductivity is intermediate between that of a metal and an insulator; its conductivity increases with temperature and in the presence of impurities)
Holonyms ("Si" is a substance of...):
quartz (a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities)
clay (a very fine-grained soil that is plastic when moist but hard when fired)
feldspar; felspar (any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium)
granite (plutonic igneous rock having visibly crystalline texture; generally composed of feldspar and mica and quartz)
sand (a loose material consisting of grains of rock or coral)
silicone; silicone polymer (any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation)
Meaning:
The syllable naming the seventh (subtonic) note of any musical scale in solmization
Classified under:
Nouns denoting communicative processes and contents
Synonyms:
te; si; ti
Hypernyms ("si" is a kind of...):
solfa syllable (one of the names for notes of a musical scale in solmization)