Belonging to per, their (singular). Gender-neutral third-person singular possessive adjective, coordinate with gendered his and her.
They (singular). Gender-neutral neologistic third-person singular subject pronoun, coordinate with gendered pronouns he and she.
Them (singular) Neologistic gender-neutral third-person singular object pronoun, suggested for use in place of him and her.
In accordance with, as per
For each.
By the, by means of the, via the, through the.
To each, in each (used in expressing ratios of units).
In a relative manner; often used when comparing array lists, where the term denotes that the items in the lists correspond to each other in the order they are given.