Without a stem or with a very short, barely visible stem; appearing stemless.
From Latin 'a-' (without) + 'caulis' (stem) + '-ous' (adjectival suffix). This is the most common English variant of the 'no stem' adjectives, using the productive '-ous' suffix.
This is the word modern botanists actually use instead of 'acauline' or 'acaulose'—language naturally favors simpler, more common suffix patterns, which is why '-ous' words usually win out over time.
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