Meaning of the word
      Taaghoot
Question

                My question is, does the term Taaghoot include objects that do not call the people to worship them, like the sun, trees, idols, stones? Also, are righteous Muslims, like Imaam Shafi', are they called Taaghoot if the people worship them or their graves?
Praise be to Allah. Not
      everything that is worshipped instead of Allaah can be considered to be
      taaghoot. The most correct scholarly view concerning the meaning of the
      word Taaghoot is that of Ibn Jareer al-Tabari, who said in his Tafseer
      (3/21):
The
      correct opinion concerning Taaghoot, in my view, is that it refers to
      everyone who arrogates to himself a position that is befitting only for
      Allaah, and so is worshipped instead of Him, either by forcing others to
      worship him or by accepting their willing worship. The one that is thus
      worshipped may be a human being, or a shaytaan (devil), or an idol, or a
      statue, or some other being.
 He
      also said that the root of Taaghoot implies putting oneself in a higher
      position and overstepping the mark.
 The
      Prophets, scholars, righteous people and awliyaa’ (those who are close
      to Allaah) did not force people to worship them or obey them in such a
      thing. On the contrary, they issued the sternest warning against it. The
      purpose behind Allaah’s sending Messengers to mankind was to call them
      to believe in Allaah alone and to disbelieve in other gods besides Him.
      Allaah says (interpretation of the meaning):
“And verily, We have sent among every Ummah
      (community, nation) a Messenger (proclaiming): ‘Worship Allaah (Alone),
      and avoid (or keep away from) Taaghoot (all false deities, etc. i.e., do
      not worship Taaghoot besides Allaah)…” [al-Nahl 16:36] 
And
      Allaah says (interpretation of the meaning):
“And
      (remember) when Allaah will say (on the Day of Resurrection): “O
      ‘Eesaa (Jesus), son of Maryam (Mary)! Did you say unto men: ‘Worship
      me and my mother as two gods besides Allaah?’ ” He will say:
      “Glory be to You! It was not for me to say what I had no right (to say).
      Had I said such a thing, You would surely have known it. You know what is
      in my inner‑self though I do not know what is in Yours; truly, You,
      only You, are the All‑Knower of all that is hidden (and unseen).  “Never
      did I say to them aught except what You (Allaah) did command me to say:
      ‘Worship Allaah, my Lord and your Lord.’ And I was a witness over them
      while I dwelt amongst them, but when You took me up, You were the Watcher
      over them; and You are a Witness to all things” [al-Maa’idah
      5:116-117]
If
      people worship Prophets or scholars instead of Allaah, we should not apply
      the word Taaghoot to the object of their worship.
If people exaggerate
      about al-Shaafa’i or any other scholar (may Allaah have mercy on them),
      and call upon them for help instead of Allaah, or worships their graves,
      there is no sin on those scholars; on the contrary, the burden of sin is
      on the one who associates others in worship with Allaah (Shirk).
      The same is true in the case of the Christians who worship ‘Eesaa (Jesus
      – peace be upon him) alongside Allaah. ‘Eesaa (peace be upon him) will
      not bear any part of their burden of sin. A brief definition of Taaghoot
      is: whoever is worshipped instead of Allaah and accepts that. It is well
      known that ‘Eesaa (peace be upon him) and other Prophets, and also
      al-Shaafa’i and other scholars who believed in Allaah alone (Tawheed)
      would never accept to be worshipped instead of Allaah. On the contrary,
      they forbade that and preached the message of Tawheed. Allaah says
      (interpretation of the meaning):
“And (remember) when Allaah will say (on the Day of
      Resurrection): “O ‘Eesaa (Jesus), son of Maryam (Mary)! Did you say
      unto men: ‘Worship me and my mother as two gods besides Allaah?’ ”
      He will say: “Glory be to You! It was not for me to say what I had no
      right (to say). Had I said such a thing, You would surely have known it.
      You know what is in my inner self though I do not know what is in Yours;
      truly, You, only You, are the All Knower of all that is hidden (and
      unseen).  “Never did I say to them aught except what You
      (Allaah) did command me to say: ‘Worship Allaah, my Lord and your
      Lord.’ And I was a witness over them while I dwelt amongst them, but
      when You took me up, You were the Watcher over them; and You are a Witness
      to all things” [al-Maa’idah 5:116-117].
And
      Allaah knows best.