In transitive terms the difference between sie and sire
is that
sie is to sift while
sire is of a male: to procreate; to father, beget.
As verbs the difference between sie and sire
is that
sie is to sink; fall; drop while
sire is of a male: to procreate; to father, beget.
As nouns the difference between sie and sire
is that
sie is a drop while
sire is a lord, master, or other person in authority, most commonly used vocatively: formerly in speaking to elders and superiors, later only when addressing a sovereign.
As a pronoun sie
is
Gender-neutral (or multigendered) subject pronoun, grammatically equivalent to the gendered pronouns he and she, or singular they