Should not (negative auxiliary)

(informal) Something that should not be done.

(idiomatic) To snub, resist or reject somebody; to regard somebody distantly.

(intransitive, Canada, US) To look backwards over one's shoulder while driving or biking, before changing lanes or making a turn, to see if any vehicles are in one's blind spots.

(Canada, US) An instance of looking backwards over one's shoulder while driving or biking, before changing lanes or making a turn, to see if any vehicles are in one's blind spots.

Contraction of should have.

A verge to the side of a highway, which should be used only in case of an emergency (especially on a motorway)

(idiomatic) Used to express gratitude at unnecessary generosity, especially when receiving a gift.

(archaic) second-person singular simple past form of shall

Do not criticize others if you have similar weaknesses yourself.