The suffix -baar productively forms adjectives out of verbs. An exception is vruchtbaar fertile, which has a nominal base, i.e. vrucht fruit (this word reflects the etymology of the affix; the original meaning of -baar was 'bearing'). Another nominal base can be found in zichtbaar visible, which is a loan from German. A special case is dierbaar precious, whose base is not an existing word of Dutch.

The meaning of the -baar-adjectives is 'possible to be X-ed' (passive) with transitive and unergative verbs (draagbaar portable < dragen to carry, werkbaar workable < werken to work), and 'able to X' (active) with intransitive verbs (ontvlambaar inflammable < ontvlammen ignite, vloeibaar liquid < vloeien flow).

If the semantics allow it, -baar adjectives can appear in the comparative and the superlative: deze kleding is betaalbaarder these clothes are more affordable.

The bases that the suffix attaches to are mostly Germanic (brandbaar inflammable < branden to burn). Some are non-Germanic (reduceerbaar reducible > reduceren to reduce). They can be morphologically simple (aaibaar cuddly < aaien to pet) or complex (aanraakbaar touchable < aanraken to touch, analyseerbaar analysable < analyseren to analyse).

The affix has a functional competitor, -(e)lijk.

Phonologically, -baar is a non-cohering suffix, it behaves as a phonological word of its own. -baar-adjectives are usually stressed on the last syllable before the suffix, which means that polysyllabic bases with initial stress are assigned a new stress pattern ( /ˈtoelaten/ permit vs. /toeˈlaatbaar/ permissible. This regularity holds for all particle verbs, as opposed to prefixed verbs which keep their stress pattern ( /weerˈleggen/ refute > /weerˈlegbaar/ refutable). Exceptions are compounds such as ˈonderverhuurbaar sublettable which retain their stress pattern even after addition of -baar.

Adjectives ending in -baar can be negated by using the prefix on- (onverstaanbaar unintelligible) or they can be nominalized with the suffix -heid (onontkoombaarheid inescapability). Negated forms inherit the particular semantics of their base: drinkbaar drinkable often means 'pleasant to drink' rather than 'possible to drink'; consequently, ondrinkbaar undrinkable usually means 'unpleasant to drink' rather than 'unsafe to drink'. Some -baar adjectives beginning with the negative prefix on- lack a positive form without this prefix (onontkoombaar inescapable - ?ontkoombaar escapable).