Table 1.

Key concepts in plant cell polarity

Term	Description
Cell polarity	Regulated asymmetric distribution of cellular components and structures along an axis
Polarity field	Individual cell polarities coordinated across tissues and organs
Polarity regulator	Contributes to polar domain formation and polar protein localization
Polarity effector or client	Uses pre-existing polar domains for localization
Axial polarity	Stable polarity axes aligned with the major body axes
Localized growth polarity	Polarity axis that determines the direction of and sustains (out)growth in specific cell types
Transient polarity	Transient polarity axis that determines morphological and/or fate asymmetry of cell division in specific cell types
Symmetry-breaking	Stimuli-induced or spontaneous initial local asymmetry that orients the polarity axis and initiates the polarization program
Reinforcement	Amplification of the initial asymmetry into stable polar domains via positive feedback and inhibitory mechanisms
Implementation	Recruitment of effectors to polar domains that drive polarization of cellular components, processes, and functions