1. Head-final compounding

The last root is the head, with modifying lexemes appended to the beginning of the word.

Negation is the prefix eng- (root #97), giving free antonyms: eng + vit → engevit “ignorance.”

2. Word-class markers

Roots are class-neutral. A final marker sets the class. These are inflectional dressing, not extra roots.

Why -igr not -inn, and -an not -a? The obvious Norse endings collide with the root inn (#99) and with root-final -a (auga, eyra). The collision-free endings were proven necessary by the round-trip validator.

3. Noun cases (four cases × two numbers)

Case marking is what lets word order be free: the subject stays nominative wherever it sits. Consonant-final stems take the ending directly; vowel-final stems insert an epenthetic þ before a vowel-initial ending.

Nom.Sg, Dat.Sg, Nom.Pl and Dat.Pl are the authentic Old Norse hestur endings; Acc and Gen are regularized so every cell is uniquely parseable. Recall the genitive húss is pronounced [husː] by the compensatory length rule.

4. Verbs (tense only, no agreement)

Verbs mark tense only — no person/number agreement, since the case system already marks who does what. This avoids the heavy Old Norse endings like -uðu.

5. Adjectives

Degree. Comparative -ari, superlative -astr, both regular and invariant: sterk → sterkari “stronger,” sterkastr “strongest.”

Agreement. An attributive adjective agrees with its noun in case & number (not gender — Rótmál nouns have none). The form is the stem-extender -ig- plus the noun's own case ending. A predicate adjective stays in the bare -igr form.

So sterkigt drótt “a strong lord” (acc.sg), sterkigum drótum “to strong lords” (dat.pl).

6. Modal particles & mood

Mood (should / could / will / want) is carried by modal particles, not an inflected subjunctive. They precede the main verb.

7. Sandhi (boundary sound-changes)

When two roots meet, the seam is smoothed — but every rule is reversible.

To parse a word: strip the class/case marker, then repeatedly match the longest legal root prefix while undoing seam effects. Because each rule leaves a recoverable trace (echo vowel, geminate length, restorable voicing), the result is always the unique original root sequence.

8. Word order (Verb-Second)

Main clauses are V2: exactly one constituent precedes the finite verb, and it can be the subject, object, or an adverbial. The verb is pinned to second position; if something else is fronted, the subject follows the verb.

Function words — conjunctions (ok and, en but), prepositions (til, frá, í, á), pronouns, the relative sem, the complementizer at — are a closed set and do not count against the 100 roots.