1. The third letter of the Greek alphabet. See Table at alphabet.
2. The third item in a series or system of classification.
3. A unit of magnetic intensity equal to one hundred thousandth (10-5) of an oersted.
4. A unit of mass equal to one millionth (10-6) of a gram.
1. Being in the third position relative to a designated carbon atom in an organic molecule at which an atom or a group may be substituted.
2. Referring to the third of a group of isomers, or molecules of similar origin or properties, determined arbitrarily by those who discover or classify them. Used in combination.
[Middle English, from Greek, of Phoenician origin; see gml2 in the Appendix of Semitic roots.]
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