Definition of first-order in US English:



  • 1Relating to the simplest or most fundamental level of organization, experience, or analysis; primary or immediate.

    ‘for a teacher, of course, drama must be a first-order experience’
    • ‘These first-order questions about the fundamental architecture and evolution of Laurentia have presented themselves loud and clear since the 1975 paper of Christie et al., yet they remain unresolved.’
    • ‘The regional crisis proved that concerns like human-rights abuses, lawlessness, and ideological extremism could quickly mount into first-order geopolitical crises.’
    • ‘For example, a first-order scarcity can be managed by desert communities because they have developed social institutions as coping strategies.’
    • ‘It is not necessary to try to ascend to a level of second-order reasons (for acting on first-order reasons) in a desperate bid to render this conception of action intelligible.’
    • ‘Unlike first-order theories, the tool chest of a mathematics educator can never be complete.’
    • ‘Now, the problem is simply this: If a person can be conflicted at the level of her first-order desires, she can also be conflicted at the second, or even at higher-orders.’
    • ‘This is because one or more of the kinetic processes of the drug (absorption, distribution, and/or elimination) may be via a process other than simple first-order kinetics.’
    • ‘Lateral branches growing directly from the primary trunk are designated first-order branches.’
    • ‘This makes is seem inevitable that the scanning device which supposedly generates higher-order experiences of our first-order visual experience would have to be almost as sophisticated and complex as the visual system itself.’
    • ‘The simple first-order political discriminator experiences no conflict in categorizing disvaluees as inferior beings to be suppressed and exploited.’
    • ‘‘There shouldn't be any sense that there's a first-order culture in the large cities and a slightly second-order culture everywhere else in the country,’ he explains.’
    • ‘Gödel proved inductively that every primitive recursive function can be simply represented in first-order number theory.’
    • ‘While indeed true, these interests might be considered immediate or first-order.’
    • ‘It mixes first-order statements about rights and responsibilities with second-order legal arrangements and often vague policy aspirations.’
    • ‘His primary concerns are the first-order issues, such as dispelling the misconceptions about the peace process.’
    • ‘It is possible to include a first-order approximation of mass transport influence in the distribution analysis, based on compartment models.’
    • ‘Moreover, in the largest trees, it was not always clear if it was the primary root or a first-order lateral that formed the observed main axis.’
    1. 1.1technical Having an order of one, especially denoting mathematical equations involving only the first power of the independent variable or only the first derivative of a function.
      • ‘Here, a series of first-order partial differential equations are set up to quantify the steady- and unsteady-state flux corresponding to the cells in the free stream, the rolling cells, and the firmly adherent cells.’
      • ‘The dynamics are therefore described by the following first-order, linear differential equations for the growth of and switching between the two subpopulations’
      • ‘The model for kinetics of digestion was a simple first-order kinetic equation with a discrete lag time.’
      • ‘The first-order rate equation can be used under conditions where micro-organisms become acclimatized to the chemical and can actively use it.’
      • ‘In the 1815 paper, which Pfaff submitted to the Berlin Academy on 11 May, he presented a transformation of a first-order partial differential equation into a differential system.’