sai

As a verb says

is third-person singular of say.

As a noun sai is

a handheld weapon with three prongs, used in some Oriental martial arts.

As a verb tell

is (lb) to count, reckon, or enumerate.

As a noun tell

is a reflexive, often habitual behavior, (especially) one occurring in a context that often features attempts at deception by persons under psychological stress (such as a poker game or police interrogation), that reveals information that the person exhibiting the behavior is attempting to withhold or tell can be (archaeology) a mound, originally in the middle east, over or consisting of the ruins of ancient settlements.

As a pronoun sai is

in this;.

As a pronoun sai

is in this;.

As a noun vendor is

a person or a company that vends or sells.

As nouns the difference between sai and trident

is that sai is a handheld weapon with three prongs, used in some Oriental martial arts while trident is a three-pronged spear somewhat resembling a pitchfork.

As nouns the difference between sai and saj

is that sai is a handheld weapon with three prongs, used in some Oriental martial arts while saj is an Asian tree, Terminalia elliptica