residual

Etymology

Recorded since 1570. From residue, itself borrowed during the Middle English period from Old French residu (Modern French résidu), from Latin residuum (“a remainder”), the neuter inflection of residuus (“remaining, left over”), perfect participle of resideō (“to remain behind”), from re- (“back, again”) + sedeō (“to sit, to reside”).

adj

1. Of, relating to, or remaining as a residue; left over.
   Yet certain films leave a residual memory—such as Psycho: many people still feel uneasy showering in a motel bathroom. 1983, Richard Ellis, The Book of Sharks, Knopf, page 185

noun

1. A remainder left over at the end of some process.
2. (in the plural) Payments made to performers, writers and directors when a recorded broadcast is repeated.
3. (statistics) the difference between the observed value and the estimated value of the quantity of interest
4. (paranormal) A spiritual presence left behind in a place as a result of a person's death or some other significant event.