anal fissure a split or tear in the lining of the anus, at the junction between inside and outside
anorectal outlet the rectum and anal canal, through which faeces is expelled
anus (also anal canal) the short, final component of the large intestine
ascending colon the right side of the colon, immediately beyond the caecum
bowel in medical terminology, synonymous with intestine; in everyday language, refers to the large intestine
caecum the first part of the large intestine
colon the first and longest part of the large intestine; comprises the caecum, the ascending colon, the transverse colon, the descending colon and the sigmoid colon
colonic lavage a commercially available rectal irrigation technique administered by registered nurses
colonic transit time the time it takes faeces to move through the large intestine, from entering the caecum to being expelled through the anus
colonoscopy examination of the colon using a long, flexible telescope inserted through the anus
defecation the act of emptying the bowel
descending colon the left side of the colon joining transverse and sigmoid colon
faecal impaction when a hard mass of stool becomes stuck in the bowel due to chronic constipation
faeces the contents of the large intestine
flatus the gas passed out of the large intestine
insoluble fibre fibre found in foods that remain crunchy even when placed in liquid (nuts, fruit peel and pulp, many vegetables); this type of fibre tends to be more stimulating to our bowels than soluble fibre, and encourages softer stools
large intestine (also large bowel) starts where the small intestine ends; comprises the colon, the rectum and the anus
lavage see colonic lavage
mass movements muscle-contraction waves that propel faeces through the colon
overflow incontinence of faeces in cases of severe constipation, a tendency for softer faecal material to slip between or around the solid masses of constipated stool and leak out of the anus
perianal skin the skin around the anus
peristaltic (of muscle contractions) wave-like
pre-emptive defecation obliging one’s bowel to work when there is no natural urge to do so
premature defecation anticipating the working of one’s bowel when the urge is still some way off
rectal irrigation the instillation of warm tap water into the rectum to effect rectal emptying
recto-anal inhibitory reflex a reflex that relaxes the internal anal sphincter muscle when faeces descends into the lower rectum in anticipation of imminent evacuation
rectum part of the large intestine, approximately 12 cm in length, joining the colon to the anus
sigmoid colon the last component of the colon, usually a tortuous segment joining the descending colon to the rectum
small intestine (also small bowel) starts where the stomach ends and continues until the large intestine begins
soluble fibre fibre found in foods that are soft and that soften further when soaked in liquid (bran, porridge, psyllium husks); this type of fibre tends to encourage bulky and well-formed stools
speculative defecation attempting to defecate in response to a sensation that is not a true and pressing urge
stool the faeces passed out during a bowel action
stool frequency the number of bowel actions an individual has in a given period of time – per day or per week
transverse colon the central component of the colon joining the ascending and descending colon
urge incontinence of faeces inability to control the sudden urge to evacuate stools that have become excessively liquid and pressingly urgent to pass