Etymology
Advertisement
filthy (adj.)

late 12c., fulthe, "corrupt, sinful," from filth + -y (2). Meaning "physically unclean, dirty, noisome" is from late 14c. Meaning "morally dirty, obscene" is from 1530s.

In early use often hardly more emphatic than the mod. dirty; it is now a violent expression of disgust, seldom employed in polite colloquial speech. [OED]

Related: Filthily; filthiness.

Related entries & more 
Advertisement
squalid (adj.)

1590s, from French squalide and directly from Latin squalidus "rough, coated with dirt, filthy," related to squales "filth," squalus "filthy," squalare "be covered with a rough, stiff layer, be coated with dirt, be filthy," of uncertain origin. Related: Squalidly; squalidness; squalidity.

Related entries & more 
dirty (v.)

"to defile; make filthy," 1590s, from dirty (adj.). Related: Dirtied; dirtying.

Related entries & more 
hoggish (adj.)
"having the characteristics of a hog," especially "gluttonous, greedy," late 15c., from hog (n.) + -ish. Meaning "slovenly, filthy" is from 1540s. Related: Hoggishly; hoggishness.
Related entries & more 
squalor (n.)
1620s, "state or condition of being miserable and dirty," from Latin squalor "roughness, dirtiness, filthiness," from squalere "be filthy" (see squalid).
Related entries & more 
Advertisement
Augean (adj.)
"very filthy," 1590s, in reference to Augean stable, the cleansing of which was one of the labors of Herakles, from Greek Augeias, from Augeas, king of Elis, whose proverbially filthy stable contained 3,000 oxen and had gone uncleansed for 30 years. Herakles purified it in one day by turning the river Alpheus through it. The name probably is from auge "splendor, sunlight."
Related entries & more 
lazar (n.)
"filthy beggar, leper," c. 1300, from Medieval Latin lazarus "leper," from Lazarus (q.v.), the name of the beggar in the biblical parable. Sometimes also lazard, with pejorative suffix.
Related entries & more 
scummy (adj.)

"covered with scum," 1570s, from scum + -y (2). Transferred sense of "filthy, disreputable" is recorded from 1932. Related: Scumminess.

Related entries & more 
ordure (n.)

late 14c., "dung, excrement, feces; filth, dirt," from Old French ordure "filth, uncleanliness" (12c.), from ord, ort "filthy, dirty, foul," from Latin horridus "dreadful" (see horrid). Related: Ordurous.

Related entries & more 
foulness (n.)
Old English fulness "foulness, filthy smell;" see foul (adj.) + -ness. Similar formation in Old Frisian fulnisse, Dutch vuilnis, German fäulniss.
Related entries & more