The jilbab is an outer garment which covers the whole body. This definition is discerned from a lexical and textual basis:
Lexical description of jilbab as an Outer Garment:
The nature and description of the jilbab can be understood from the lexical definition of the word jilbab as explained in classical Arabic dictionaries. These sources also explain the function of the jilbab as an outer garment:
“The jilbab is the outer garment, mantle, or cloak. It is derived from the verb tajallbaba, which means to clothe. Jilbab is the outer sheet or covering which a woman wraps around her on top of her garments to cover herself from head to toe. It hides her body completely”
“The jilbab…is that which conceals the clothes like a cover”
As for modern dictionaries it is worth citing from the monumental work of the 19th-century British scholar and lexicographer Edward William Lane (1801-76):
Arabic-English Lexicon: ‘jilbab: …one that envelopes the whole body: (TA) and a wide garment for a woman, less than the milhafah (sheet): or one with which a woman covers over her other garments…’
This description has also been given in the Oxford Dictionary of Islam edited by John L. Esposito where it states:
Jilbab Generic term for women’s outer garment (shawl, cloak, wrap) in Arabian sedentary communities before and after the rise of Islam. The Qur’an (333:59) instructs Muslim women to cloak themselves as a mark of status and as a defensive measure against sexual harassment in public places.
The textual definition as enunciated by the law giver is of jilbab as an outer garment.
The reasons for concluding that the jilbab is an outer garment are textual as well as linguistic. What is meant by textual in this context is the primary corpus of Islamic legal text obligated by the law giver i.e. the Qur’an and the practise of Prophet Muhammad. So for example in chapter 24 the following verse gives elderly women the option to set aside their outer garment:
The garment mentioned must be an outer garment as the verse could not possibly be saying they should discard their normal everyday clothing. That is why companions of Muhammad, such as Ibn ‘Abbas and Ibn Mas’ud, both understood the garment to refer to the jilbab, since that is the outer garment that is worn by women. Both of whom are considered experts in Quran exegesis.
Authority for it as an outer garment is also to be found in the Sunnah. The above report of Umm ‘Atiyyah is clear in its indication that the jilbab is an outer garment. This is because the Prophet stipulated that before going out she needs to wear a jilbab and if she does not have one she must ‘…borrow the jilbab of her companion”.
The fact that she was not allowed to go outside without it indicates its function as an outer garment.
Also Abu Dawud records a report on the authority of Umm Salama (a wife of the Prophet) which indicates that jilbab is an outer garment. It is reported that she asked the Prophet: “Can a woman pray in a long dress and a headscarf without wearing an izar (a type of jilbab)?” He (pbuh) replied, “If the long dress is ample and covers the surface of her feet.” (Abu Dawud) The fact that Umma Salmah asked if she can wear a long dress and headscarf without the izar (jilbab), this indicates that the izar (jilbab) is normally worn on top of the regular clothes.
This is supported by the view of companions who said that the clothing of women during prayer is the above three items, which means the izar (jilbab) must have been worn above the normal clothes. So for example it is narrated that Umar (ra) said: ‘The woman should pray in three items of clothing: long dress, headscarf and izar (jilbab).’ It is also reported that his son Abdullah b. Umar said: ‘The woman should pray wearing long dress, headscarf and milhafa (jilbab).’
It is due to the above narrations that Al-Shirazi took the view that the jilbab is the outer garment as the following excerpt shows: ‘It is recommended that when a woman prays that she wears three items of clothing: a headscarf by which to cover the head and neck. A dress to cover the body and feet and a milhafa (jilbab) by which to cover her clothes. This is due to the report that Umar (ra) said: ‘The woman should pray in three items of clothing: dress, headscarf and izar (jilbab).’ It is also reported that Abdullah b. Umar who said ‘The woman should pray wearing dress, headscarf and milhafah (jilbab).’ Also, it is recommended that her jilbab is thick so that it does not describe parts of her body and does not move away when she assumed the bowing and prostration positions so that it does not describe her clothes.’
An-Nawawi (d.676), a commentator of Al-Shirazi’s Muhazzab explained the latter’s comments and attributed it to Shafi’i (the founder of the Shafi’i school of thought): ‘This ruling has been stated by ash-Shafi’i and the scholars of the school are agreed on this.’ Then he quotes the view that the jilbab: ‘is a sheet worn over the clothes i.e. that it is an outer garment)’ saying: ‘This view is correct and it is the view of ash-Shafi’i (i.e. that the jilbab is worn over the ones clothes).
Ibn Hazm stated in his al-Muhalla: ‘In the Arabic language of the Prophet, jilbab is the outer garment which covers the entire body. A piece of cloth which is too small to cover the entire body could not be called jilbab.
Thus, the fact that the jilbab is an outer garment is established by the Qur’an and Sunnah and it is the same meaning understood by the companions of Muhammad (pbuh) and attested by the scholars.
There are other conditions which are not specific to jilbab but generally applicable to all clothing when women go before non-mahrams (close relations to whom marriage is impermissible) whether inside or outside the home. They are the following:
i. It must be loose-fitting
ii. Should not be semi-transparent
iii. Should not become an attraction (tabarruj)
iv. Should not resemble the clothing of men.
These conditions are well known and accepted and there is no need to dwell on them, for further discussion of their evidences one can consult the relevant books of Islamic jurisprudence.