Not fitting neatly into either of two categories or positions. / Used other than figuratively or idiomatically: see between, two, stool.

(medicine) Bristol stool chart

plural of Bristol stool scale

(medicine) A symptom of severe phosphorus poisoning in which stools (feces) laden with phosphorus are passed.

(medicine) A chart (and associated scale) that classifies human faeces, with limited use as a diagnostic aid.

plural of Bristol stool chart

Unable to fit into either of two conflicting categories, and as a result likely to fail.

simple past tense of fall between two stools

past participle of fall between two stools

Third-person singular simple present indicative form of fall between two stools