Cf.It seems to be a noun suffix denoting instrument, vessel/place or a person (very rare).
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Here's a list of them: https://en.wiktionary.org/wiki/Category:Latin_words_suffixed_with_-braCf.
latebra hiding place / lateo to be hidden
salebra jolting place / salio to spring
dolabra pickaxe / dolo to chip with an axe
&c&c.
Does the Latin suffix -bra have a meaning?
It seems that if you go far enough back, Latin -bra, -brum, and -trum, as well as Greek -tron (as in to arotron, "a plow") are all related as instrumental suffixes, coming from alternate forms (one with the voiced initial, one with unvoiced) of the same IE instrumental suffix.It's a regular variant of the suffix -blo- (vestībulum), itself a variant of -tro-, tlo- (arātrum, titulus), with -tlo- giving a further variant -clo-/-cro- (novācula, simulācrum), all exhibiting the the R-L dissimilation: pick /l/ if there's an /r/ in the stem and vice versa.