Sample Size
Etymology
“Sample” is an aphetic form of Old French “essample” (example), from Latin “exemplum” (a specimen taken to represent the whole). “Size” is from Old French “sise,” a shortening of “assise” (a sitting, a settled amount).
noun phrase · /SAM-puhl SYZE/
The number of observations a conclusion is based on.
What it names
It is the first thing to check before trusting any statistic — a striking result from tiny data is usually just noise.
Example
A miracle diet that worked for eight people has a sample size too small to distinguish real effect from luck.
Related idea
Small samples breed false patterns and feed regression to the mean; a large sample size narrows the margin of error, but it cannot fix a biased sample — a huge but skewed poll is still wrong.