The quality or state of being half; incompleteness, partiality, or the condition of existing in a bisected state.
From 'half' + '-ness' (nominalizing suffix). This abstract noun formation allows 'half' to become a quality that can be discussed philosophically, similar to how 'wholeness' expresses completeness.
Halfness is a deliciously philosophical word—it captures not just 'being divided' but the entire philosophical concept of incompleteness and partiality. Medieval scholars loved words like this for contemplating existence and essence.
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