Which languages are “nnl.”, “altn.” and “schw.”?

Question

What do the abbreviations "nnl.", "altn." and "schw." mean in the context of etymology?

Other abbreviations in the same paragraph were "mhd." (mittelhochdeutsch) and "ags." (angelsächsisch). My guess is that "altn." is Altnordisch and "schw." is Schwäbisch, but I have no idea about "nnl.".

Answer 1

In an etymological context the abbreviations you found mean:

altn.
altnordisch

altn.
altniederländisch

nnl.
neuniederländisch

schw.
Dafür gibt es unterschiedliche Verwendungen: Im nordischen Kontext "schwedisch", evtl. auch "schweizerisch" oder "schwäbisch".

Note: the abbreviation schw. also means schwach [gebeugt] in dictionaries.