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the 9th letter of the Roman alphabet
letter of the alphabet
the conventional characters of the alphabet used to represent speech
the smallest whole number or a numeral representing this number
a singular metaphysical entity from which material properties are said to derive
a single object (as distinguished from a pair)
one of a pair
one of the elements that collectively form a system of numeration
a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks)
atomic number 53
heavy radioactive isotope of iodine with a half-life of 8 days; used in a sodium salt to diagnose thyroid disease and to treat goiter
light radioactive isotope of iodine with a half-life of 60 days; used as a tracer in thyroid studies and as a treatment for hyperthyroidism
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
any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions
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