As nouns the difference between titer and taper
is that
titer is (analytical chemistry) the concentration of a substance as determined by titration while
taper is a slender wax candle; a small lighted wax candle; hence, a small light or
taper can be (weaving) one who operates a tape machine.
As verbs the difference between titer and taper
is that
titer is to measure a concentration, especially by means of titration while
taper is to make thinner or narrower at one end.