What's the difference between often and once?

Often


Definition:

  • (adv.) Frequently; many times; not seldom.
  • (a.) Frequent; common; repeated.

Example Sentences:

  • (1) Previous use of the drug is found in more than 50 per cent of the patients, and it was often followed by a neglected side-effect.
  • (2) Two of the largest markets are Germany and South Korea, often held up as shining examples of export-led economies.
  • (3) The pattern of the stressor that causes a change in the pitch can be often identified only tentatively, if there is no additional information.
  • (4) The sound of the ambulance frightened us, especially us children, and panic gripped the entire community: people believe that whoever is taken into the ambulance to the hospital will die – you so often don’t see them again.
  • (5) However, the groups often paused less and responded faster than individual rats working under identical conditions.
  • (6) But RWE admitted it had often only been able to retain customers with expired contracts by offering them new deals with more favourable conditions.
  • (7) These cells contained organelles characteristic of the maturation stage ameloblast and often extended to the enamel surface, suggesting a possible origin from the ameloblast layer.
  • (8) They can rarely be detected spontaneously but most often are provoked.
  • (9) Providers used the tests significantly more often to evaluate patients with cancer risk factors or for new patients.
  • (10) The younger patients more often experienced an acute arthritis with sacroiliitis resembling a reactive disease.
  • (11) Our findings indicate that Turner girls have a functional brain disorder more often than the controls, particularly at the occipital and parietal areas and in those with hemispheric differences most often in the right hemisphere.
  • (12) Lactate-induced anxiety and symptom attacks without panic were seen more often in the groups with panic attacks, but a full-blown panic attack was provoked in only four subjects, all belonging to the groups with a history of panic attacks.
  • (13) During these delays, medical staff attempt to manage these often complex and painful conditions with ad hoc and temporizing measures,” write the doctors.
  • (14) Women seldom occupy higher positions in a [criminal] organisation, and are rather used for menial, but often dangerous tasks ,” it notes.
  • (15) Delineation of the presence and anatomy of an obstructed, nonfunctioning upper-pole duplex system often requires multiple imaging techniques.
  • (16) Damage to this innervation is often initiated by childbirth, but appears to progress during a period of many years so that the functional disorder usually presents in middle life.
  • (17) Even today, our experience of the zoo is so often interrupted by disappointment and confusion.
  • (18) Diagnosis and identification of the site of the leak is often inaccurate, even with meticulous care given to placing and removing the nasal pledgets.
  • (19) He was reclusive, I know that, and he was often given a hard time for it.
  • (20) Also, it is often the case that trustees or senior leadership are in said positions because they have personal relationships with the founder.

Once


Definition:

  • (adv.) By limitation to the number one; for one time; not twice nor any number of times more than one.
  • (adv.) At some one period of time; -- used indefinitely.
  • (adv.) At any one time; -- often nearly equivalent to ever, if ever, or whenever; as, once kindled, it may not be quenched.

Example Sentences: