I. noun
or ti·tre ˈtī]d.ə(r), ]tə- sometimes ˈtē]\
( -s )
Etymology: French titre title, designation of rank, proportion of gold or silver in a coin, from Middle French title, tiltre title, designation of rank, from Old French title — more at title
1. : the strength of a solution or the concentration of a substance in solution as determined by titration and usually expressed as the reciprocal of the highest dilution of the solution or substance showing specific activity
2. : the solidifying point of the fatty acids liberated from a fat that is determined by melting the acids in a tube and noting the temperature at which they solidify again on cooling
II. noun
: the dilution of a serum containing a specific antibody at which the solution just retains a specific activity (as neutralizing or precipitating an antigen) but loses it at any greater dilution