The prefix wjer- creates nouns on the basis of other nouns. It means something like counter, against or in return. Prefixations with wjer- are listed below:

Base form	Derivation
heak hook	wjerheak barb
fraach question	wjerfraach counterquestion
klang sound	wjerklang echo
sin liking	wjersin aversion
wurd word	wjerwurd reply
skyn shine	wjerskyn reflection
stân state	wjerstân aversion
kant side	wjerskanten both sides
leafde love	wjerleafde love in return
glâns glow	wjerglâns reflection
lûd sound	wjerlûd dissenting opinion
angel fsting	wjerangel barb

The derivation wjerskanten both sides is somewhat typical. It is a plurale tantum and restricted to the adpositional expressions fan wjerskanten from both sides and oan wjerskanten on both sides. Moreover, it shows a linking element -s-. The word wjergea equal has a base that has become obsolete.

The affix wjer- should not be confused with the verbal particle wer again, which can be found in nominalizations of particle verbs. Examples are werprintinge reprint, werdoper anabaptist, werkomst return or weropbou rebuilding.

Both elements derive from the Old Frisian root wither. This adverb could occur independently, but could also be used as a prefix in verbal and nominal derivations. One can find it as such in Frisian texts from the Middle Ages in forms like witherbringa to bring back, witherjeva to give back and witherwird reply. The seventeenth century writer Gysbert Japicx spells both words as weer, so it seems that the forms still overlapped in that time. The prefix wjer- has extricated itself in form and function from wer-. While wer again exists as an independent element, wjer- against can only show up as a prefix. It is likely that wjer- is a broken variant of the seventeenth century weer (and wer is possibly a shortened form of the same word). There are more languages in which a distinction in form and function took place, for example in German (wieder again next to wider against).

In derivations with wjer- the stress is on the prefix, for example WJERwurd reply. The prefix is pronounced as [vjɛr]. People from the southern part of the province of Fryslân leave out the [j] when pronouncing wjer-, a consonant cluster simplification not uncommon in the relevant dialects.