Etymology From Middle English gnawen, gnaȝen, from Old English gnagan, from Proto-West Germanic *gnagan, from Proto-Germanic *gnaganą (“to gnaw”), probably from Proto-Indo-European *gʰnēgʰ- (“to gnaw, scratch”). Cognate with Dutch knagen, German nagen, Danish gnave (“to gnaw”), Norwegian Bokmål gnage, Norwegian Nynorsk gnaga, Swedish gnaga.
1
Ambitransitive To bite something persistently, especially something tough.
The dog gnawed the bone until it broke in two.
Ten thousand men that fishes gnaw'd uponc. 1593 (date written), William Shakespeare, “The Tragedy of Richard the Third: […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene iv], line 25:
2
To produce excessive anxiety or worry.
Her comment gnawed at me all day and I couldn't think about anything else.
3
To corrode; to fret away; to waste.
VVots thou vvho's returnd, / The unthrift Bonvile, ragged as a ſcarre-crovv / The VVarres have gnavv'd his garments to the skinne: […]1637, Thomas Heywood, The Royall King, and the Loyall Subject. […], London: […] Nich[olas] and John Okes, for James Becket, […], →OCLC, Act III, signature E4, verso:
Etymology From Middle English gnawen, gnaȝen, from Old English gnagan, from Proto-West Germanic *gnagan, from Proto-Germanic *gnaganą (“to gnaw”), probably from Proto-Indo-European *gʰnēgʰ- (“to gnaw, scratch”). Cognate with Dutch knagen, German nagen, Danish gnave (“to gnaw”), Norwegian Bokmål gnage, Norwegian Nynorsk gnaga, Swedish gnaga.