Melting temperature may refer to:
Melting temperature, the temperature at which a substance changes from solid to liquid state.
DNA melting temperature, the temperature at which a DNA double helix dissociates into single strands.
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(Tm): The temperature at which the two strands of a double-stranded DNA molecule come apart. A short (<18 nucleotides) oligonucleotides Tm value is estimated by the formula: Tm = (number of A + T)x2 + (number of G + C)x4.