'ragged'(Modern English )
This rare ME v. is generally assumed (so MED, OED3) to have been formed on the unusual n. ratt(e) 'rag, tatter', which is of obscure etymology. The only plausible etymon that has been put forward is ON (so OED3, MED, Anderson and by implication GollCl and Menner who connect it with the MnE word), cp. OIcel hrati 'rubbish, trash' (in the compound keralda-hrati) and hrat (neut.) 'refuse', which could explain the form and sense. The ult. connections of the ON word, however, are also unclear; it may or may not be related to the OIcel v. hrata 'stagger' or OE hradian 'hasten' (see further OED3, Mag.).
Proposed ON Etymon (OIcel representative)
cp. hrati (n.) 'rubbish, trash'
(ONP hrati (sb.))
Other Scandinavian Reflexes
Icel hrati, Norw rate, Sw dial rata
Phonological and morphological markers
MED's only other citation of the v. comes from a1450(?1419-20) Topias (Dgb 41) (sometimes emended away, and omitted from OED3) and the n. from a1250 Wooing Lord (Tit D.18) and Erk. The n. occurs in N dial of MnE (OED3).
Occurrences in the Gersum Corpus