Sentence:  When a substance is placed in an electric field, the molecules tend to <WSD>orient</WSD> themselves in a definite pattern with respect to the direction of the field. The dielectric constant of the material can, for simplicity, be defined as a measure of the degree to which the individual particles are <WSD>oriented</WSD> or the material polarized. 
Meaning of the word marked with <WSD> tags:  To direct towards or point at a particular direction.