Definition of posterior in US English:



  • 1Anatomy
    Further back in position; of or nearer the rear or hind end, especially of the body or a part of it.

    ‘the posterior part of the gut’
    The opposite of anterior
    ‘a basal body situated just posterior to the nucleus’
    • ‘When cool, insert a good knife or poultry shears, where the body and the tail are joined and cut towards the posterior, then turn the lobster around and cut toward the anterior.’
    • ‘When body fluids become concentrated, more antidiuretic hormone is released from the posterior lobe of the pituitary gland, and acts in the kidneys to promote retention of water.’
    • ‘The posterior lobe of the pituitary gland or neurohypophysis contains unique glial elements referred to as pituicytes.’
    • ‘Tabes dorsalis involves the dorsal roots and posterior columns of the spinal cord.’
    • ‘He had macroglossia, and a posterior position of the soft palate.’
    • ‘There was also a single, small cerebral metastasis in the white matter of the posterior occipital lobe.’
    rear, hind, back, hinder, rearward
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    1. 1.1Medicine Relating to or denoting presentation of a fetus in which the rear or caudal end is nearest the cervix and emerges first at birth.
      ‘a posterior labor’
      Compare with breech birth
      • ‘Father is especially proud of mother, who resolved to labor naturally, and did so despite a forty-two hour labor and a posterior baby.’
      • ‘Does the hands-and-knees posture during labour help to rotate the occiput posterior fetus?’
      • ‘The midwife visited this morning and the good news is that the head is engaged but the bad news is that the baby is posterior.’
  • 2formal Coming after in time or order; later.

    ‘a date posterior to the first Reform Bill’
    • ‘The Japanese data were also recently released by the Ministry of Finance of Japan but are available only for the period posterior to May 1991.’
    • ‘It would be folly, therefore, not to assign the authorship of the "Commentary" to a time posterior to the Early Edition.’
    • ‘If our recognition of a Greek idiom in Ecclesiastes is valid, it points to a date posterior to the conquest of Alexander the Great.’
    later than, subsequent to, following, succeeding, after
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  • A person's buttocks.

    • ‘By the time you stand up you feel like you have a basket weave pattern embossed on your posterior.’
    • ‘People pack the cafes to eat several courses at lunch, yet their posteriors do not require three or four chairs apiece.’
    • ‘As my posterior touches down on porcelain, I let out a sigh of relief.’
    • ‘He wriggles his posterior, as though testing the chair's rating for comfort.’
    • ‘But when it comes time to make that decision, almost 40 per cent of us fail to remove our posteriors from the couch and forfeit our voice in the nation's affairs.’
    • ‘Bureaucrats are not known for their boldness; if something bad happens, they want some sort of shelter for their posteriors.’
    • ‘My legs carried my plump, childish body to near her face, and I rested my posterior upon the ground.’
    • ‘Only once did I have a crash landing and create a hugely attractive mould of my posterior in the sand.’
    • ‘But if things do fall apart completely, we appear to be fortuitously well prepared for a descent into cannibalism judging by the plethora of plump posteriors wandering the malls.’
    • ‘In fact, it's fairly easy to tell how much a person exercises just by checking out their posterior.’
    buttocks, behind, backside, rear, rear end, rump, seat, haunches, hindquarters, cheeks
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Early 16th century (as a plural noun denoting descendants): from Latin, comparative of posterus ‘following’, from post ‘after’.