We speak of a thing as faultless, stainless, or spotless, only when we mean that it is absolutely without fault or blemish; as, a spotless or stainless reputation; a faultless course of conduct.

Webster's Revised Unabridged Dictionary (1913)

Example sentences

immaculate Skura is running an immaculate household in Algiers.
pristine Yanni's once pristine residence has become unrecognizable.
unsullied Her reputation remained unsullied.
unblemished His reputation remains unblemished.

Popularity over time

Word	1850 → 2019	Trend
spotless		rising
immaculate		rising
pristine		rising
unsullied		rising
unblemished		rising

Use in printed books, per decade from 1850 to 2019.

By length

4 letters: fair¹, pure¹
5 letters: clean¹, pyore
6 letters: chaste¹
7 letters: perfect², sinless
8 letters: innocent³, flawless², pristine²
9 letters: stainless², blameless², faultless, unsullied³, untainted³, guiltless², undefiled, unstained², unspotted
10 letters: immaculate⁴
11 letters: unblemished³, untarnished, blemishless
14 letters: irreproachable

The small number after each word is its number of syllables (perfect² = 2 syllables).