@silvertonge that hadith says about zakat only but in general ahlebayt includes wives:
Quran explicitly mentions the wives of the prophet pbuh as Ahlebayt, when the verse below was revealed then this caused the prophet pbuh to pray for the hasnain in cloak to be also included in the ahle bayt as no verse was revealed explicitly addressing them.As related in some traditions that the Holy Prophet did not cover Hadrat 'A'ishah and Hadrat Umm Salamah under the sheet of cloth which he put on the four members of his family, does not mean that he had excluded those ladies from his "household." But it means that the wives were already included in ahl al-bait, because the Qur'an, in fact, had addressed them as ahl al-bait. The Holy Prophet, however, thought that the apparent words of the Qur'an might cause somebody the misunderstanding about these members that they were excluded from the ahl al-bait. Therefore, he felt the need for clarification in their case and not in the case of his wives.
http://quran.com/33/30
O wives of the Prophet, whoever of you should commit a clear immorality - for her the punishment would be doubled two fold, and ever is that, for Allah, easy. (30)
And whoever of you devoutly obeys Allah and His Messenger and does righteousness - We will give her her reward twice; and We have prepared for her a noble provision. (31) O wives of the Prophet, you are not like anyone among women. If you fear Allah, then do not be soft in speech [to men], lest he in whose heart is disease should covet, but speak with appropriate speech. (32) And abide in your houses and do not display yourselves as [was] the display of the former times of ignorance. And establish prayer and give zakah and obey Allah and His Messenger. Allah intends only to remove from you the impurity [of sin], O people of the [Prophet's] household(Ahlebayt), and to purify you with [extensive] purification. (33)
“The context in which this verse occurs makes it manifest that the word ahl al-bait (people of the house) here implies the wives of the Holy Prophet (upon whom be Allah's peace), because the address begins with: "O wives of the Prophet," and they are the addressees in the whole discourse preceding it as well as following it. Moreover, the word ahl al-bait in Arabic is used precisely in the sense in which the word "household" is used in English, which includes both a man's wife and children. No one would exclude the wife from the "household." The Qur'an itself has used this word at two other places besides this, and at both the wife is included in its sense, rather as the most important member of the family. In Surah Hud, when the angels give the Prophet Abraham the good news of the birth of a son, his wife exclaims: "Shall I bear a child now when I have grown too old, and this husband of mine has also become old?" The angels say: What! Are you surprised at Allah's decree, O people of Abraham's household? Allah's mercy and blessings are upon you." In Surah Al-Qasas, when the Prophet Moses reaches the Pharaoh's house as a suckling, and the Pharaoh's wife is in search of a suitable nurse for the child, the Prophet Moses' sister says, "Shall I tell you of a household whose people will bring him up for you and look after him well?" Thus, the Arabic idiom and the usage of the Qur'an and the context of this verse, 'all point clearly to the fact that the Holy Prophet's wives as well as his children are included in his ahl al-bait; rather the more correct thing is that the verse is actually addressed to the wives and the children become included in the household only because of the sense of the word. That is why according to lbn 'Abbas and 'Urwah bin Zubair and `Ikrimah, the word ahl al-bait in this verse implies the wives of the Holy Prophet.
But if somebody says that the word ahl al-bait has been used only for the wives and none else can be included in it, it will also be wrong. Not only this that the word "household" includes all the members of a man's family, but the Holy Prophet has himself explained that this includes even himself. According to Ibn Abi Hatim, once when Hadrat `A'ishah was asked about Hadrat `Ali, she said, Do you ask me about the person who was among the most loved ones of the Holy Prophet and whose wife was the Holy Prophet's daughter and most beloved to him?" Then she related the event when the Holy Prophet had called Hadrat 'Ali and Fatimah and Hasan and Husain (may Allah be pleased with them all) and covered them all with a sheet of cloth and prayed: "O Allah, these are my household, remove uncleanness from them and make them pure." Hadrat 'A'ishah says, "I said: I also am included among your household (i.e. I may also be covered under the sheet and prayed for).” Thereupon the Holy Prophet replied" You stay out: you, of course, are already included." A great many Ahadith bearing on this subject have been related by traditionalists like Muslim, Tirmidhi, Ahmad, Ibn Jarir, Hakim, Baihaqi, etc. on the authority of Abu Said Khudri, Hadrat 'A'ishah, Hadrat Anas, Hadrat Umm Salamah, Hadrat Wathilah bin Aqsa' and some other Companions, which show that the Holy Prophet declared Hadrat 'AIi and Fatimah and their two sons as his ahl al-bait. Therefore, the view of those who exclude them from the ahl al-bait is not correct.
Similarly the view of those people also is not correct, who, on the basis of the above-cited Ahadith, regard the wives of the Holy Prophet as excluded from his ahl al-bait. In the first place, anything which has been clearly stated in the Quran cannot be contradicted on the basis of a Hadith. Secondly, these Ahadith also do not have the meaning that is put on them. As related in some traditions that the Holy Prophet did not cover Hadrat 'A'ishah and Hadrat Umm Salamah under the sheet of cloth which he put on the four members of his family, does not mean that he had excluded those ladies from his "household." But it means that the wives were already included in ahl al-bait, because the Qur'an, in fact, had addressed them as ahl al-bait. The Holy Prophet, however, thought that the apparent words of the Qur'an might cause somebody the misunderstanding about these members that they were excluded from the ahl al-bait. Therefore, he felt the need for clarification in their case and not in the case of his wives.
A section of the people have not only misconstrued this verse to the extent that they have made the word ahl al-bait exclusively applicable to Hadrat `AIi and Fatimah and their children to the exclusion of the holy wives, but have gone even further and concluded wrongly from its words "Allah only intends to remove uncleanliness from you and purify you completely", that Hadrat 'Ali and Fatimah and their children are infallible like the Prophets of Allah. They say that "uncleanliness" implies error and sin, and, as Allah says, these ahl al-bait have been purified of this, whereas the words of the verse do not say that uncleanliness has been removed from them and they have been purified. But the words are to the effect: "Allah intends to remove uncleanliness from you and purify you completely. " The context also does not tell that the object here is to mention the virtues and excellences of the Holy Prophet's household. On the contrary, they have been advised here what they should do and what they should not, because Allah intends to purify them. In other words, they have been told that if they adopted such and such an attitude and way of life, they will be blessed with cleanliness, otherwise not. However, if the words "Allah intends to remove uncleanliness from yon . . . " are taken to mean that Allah has made them infallible, then is no reason why all the Muslims who perform their ablutions before offering the Prayer are not held as infallible, because about them also Allah says: "But Allah wills to purify you and complete His blessings upon you." (Al-Ma'idah: 6)”. (end of quote).
So as conclusion we should say, that ahlalbayt are: of `Ali, the family of `Aqil, the family of Ja`far and the family of `Abbas, wifes of prophet (sallalahu alaihi wa ala alihi wa sallam).
These include Banul Muttalib also, for the prophet (sallalahu alaihi wa ala alihi wa sallam) has said: “They didn’t left us neither during the period of ignorance nor in the period of Islam”
