appeal vs should

appeal

verb
  • To call upon a person or an authority to corroborate a statement, to decide a controverted question, or to vindicate one's rights; to entreat, to invoke. 

  • To accuse or charge (someone) with wrongdoing (especially treason). 

  • To be attractive. 

  • To summon (someone) to defend their honour in a duel, or their innocence in a trial by combat; to challenge. 

  • Of the accomplice of a felon: to make an accusation at common law against (the felon). 

  • To have recourse or resort to some physical means. 

  • To call upon someone for a favour, help, etc. 

  • Often followed by against (the inferior court's decision) or to (the superior court): to apply to a superior court or judge for a decision or order by an inferior court or judge to be reviewed and overturned. 

  • Of a fielding side; to ask an umpire for a decision on whether a batsman is out or not, usually by saying "How's that?" or "Howzat?". 

  • To apply to a superior court or judge to review and overturn (a decision or order by an inferior court or judge). 

  • Of a private person: to instituted legal proceedings (against another private person) for some heinous crime, demanding punishment for the particular injury suffered. 

noun
  • At common law, an accusation made against a felon by one of their accomplices (called an approver). 

  • A summons to defend one's honour in a duel, or one's innocence in a trial by combat; a challenge. 

  • An application to a superior court or judge for a decision or order by an inferior court or judge to be reviewed and overturned. 

  • The act, by the fielding side, of asking an umpire for a decision on whether a batsman is out or not. 

  • The legal document or form by which such an application is made; also, the court case in which the application is argued. 

  • A process which formerly might be instituted by one private person against another for some heinous crime demanding punishment for the particular injury suffered, rather than for the offence against the public; an accusation. 

  • A call to, or the use of, a principle or quality for purposes of persuasion. 

  • An accusation or charge against someone for wrongdoing (especially treason). 

  • A person's legal right to apply to court for such a review. 

  • A call to a person or an authority for a decision, help, or proof; an entreaty, an invocation. 

  • A resort to some physical means; a recourse. 

  • A power to attract or interest. 

should

verb
  • Used to express what the speaker would do in another person's situation, as a means of giving a suggestion or recommendation. 

  • Will be likely to (become or do something); indicates a degree of possibility or probability that the stated thing will happen or be true in the future. 

  • Indicates that something is expected to have happened or to be the case now. 

  • Used to express a conditional outcome. 

  • With verbs such as 'see' or 'hear', usually in the second person, used to point out something remarkable in either a good or bad way. 

  • To make a statement of what ought to be true, as opposed to reality. 

  • Used to impart a tentative, conjectural or polite nuance. 

  • Simple past tense of shall. 

  • In questions, asks what is correct, proper, desirable, etc. 

  • Used to issue an instruction (traditionally seen as carrying less force of authority than alternatives such as 'shall' or 'must'). 

  • Used to give advice or opinion that an action is, or would have been, beneficial or desirable. 

  • Used to form a variant of the present subjunctive, expressing a state or action that is hypothetical, potential, mandated, etc. 

noun
  • Something that ought to be the case as opposed to already being the case. 

How often have the words appeal and should occurred in a corpus of books? (source: Google Ngram Viewer )