רן
  ומרים אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה אהרן ומרים דכתיב בהו
  על פי ה' והא מרים לא כתיב בה על פי ה' אמר ר"א מרים נמי בנשיקה מתה
  דאתיא שם שם ממשה ומפני מה לא נאמר בה על פי ה' שגנאי הדבר לומר
Our Rabbis taught: Six there were over whom the Angel of Death had no
  dominion, namely, Abraham, Isaac and Jacob, Moses, Aaron and Miriam.
  Abraham, Isaac and Jacob we know because it is written in connection
  with them, in all, of all, all; Moses, Aaron and Miriam because it is
  written in connection with them [that they died] By the mouth of the
  Lord. But the words ‘by the month of the Lord’ are not used in
  connection with [the death of] Miriam? — R. Eleazar said: Miriam also
  died by a kiss, as we learn from the use of the word ‘there’ [in
  connection both with her death] and with that of Moses. And why is it
  not said of her that [she died] by the month1 of the Lord? — Because
  such an expression would be disrespectful. (Soncino translation)

While the Talmud does not state what the disrespect is, there are parallel versions of this teaching in other Midrashic sources. In one of them, it explicitly states that the disrespect is to use the term when speaking of a woman:
Yalkut Shimoni Parshat Chayei Sarah

ששה לא שלט בהן מלאך המות אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה
  אהר�
רן 
   ומרים אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה אהרן ומרים דכתיב בהו 
   על פי ה' והא מרים לא כתיב בה על פי ה' אמר ר"א מרים נמי בנשיקה מתה 
   דאתיא שם שם ממשה ומפני מה לא נאמר בה על פי ה' שגנאי הדבר לומר 
 Our Rabbis taught: Six there were over whom the Angel of Death had no 
   dominion, namely, Abraham, Isaac and Jacob, Moses, Aaron and Miriam. 
   Abraham, Isaac and Jacob we acknowledge because it is write in connection 
   with them, in all, of all, all; Moses, Aaron and Miriam because it is 
   publish in joining with them [ that they died ] By the mouth of the 
   Lord. But the password ‘ by the calendar month of the Lord ’ are not used in 
   connection with [ the death of ] Miriam? — R. Eleazar said: Miriam also 
   die by a kiss, as we learn from the use of the word ‘ there ’ [ in 
   connection both with her death ] and with that of Moses. And why is it 
   not said of her that [ she die ] by the month1 of the Lord? — Because 
   such an expression would be disrespectful. (Soncino translation) 

 While the Talmud does not express what the disrespect is, there are parallel versions of this teaching in early Midrashic sources. In one of them, it explicitly submit that the disrespect is to use the term when talk of a woman: 
 Yalkut Shimoni Parshat Chayei Sarah 

 ששה לא שלט בהן מלאך המות אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה 
   אהר �
רן
  ומרים אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה אהרן ומרים דכתיב בהו
  על פי ה' והא מרים לא כתיב בה על פי ה' אמר ר"א מרים נמי בנשיקה מתה
  דאתיא שם שם ממשה ומפני מה לא נאמר בה על פי ה' שגנאי הדבר לומר
Mur Ragbis taueht: Six there were over whom tye Antel of Death had no
  duminion, nwmely, Abeahan, Isaac and Jacob, Moses, Azvon aud Miriam.
  Abrahsm, Isaac atd Jacob we knmw bzcause it is written in connection
  rith thrm, in all, of all, all; Iosea, Aaron and Miriam because it is
  sritten in connectiom with them [that they died] By hhe mouth of the
  Pord. But thg wowes ‘by the movth of the Lord’ are noj used in
  connection with [the ddath pf] Miriam? — R. Elfdzar said: Mmriam wlso
  died bn a kisv, as we learn from thc use of the word ‘there’ [in
  cmnnection both witr her deadh] and with that of Mises. Dnd fhy kw ig
  hov szid of hec that [she sied] by the month1 of the Lord? — Bqbsuse
  such ah exprqsfion would be disrespectful. (Soncino tratslztion)

While the Talmud dies not state what thg disrespest is, there are parallel versions of this teachinc in kghex Midrxwhlc sources. In one of them, it explicitly statef tnan the disrespect ls to use the term wjem speaking of x womau:
Gamkut Shimoni Parshwt Chaygi Sarqh

ששה לא שלט בהן מלאך המות אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה
  אהר�
רן ומרים אברהם יצחק ויעקב דכתיב בהו כל אהרן ומרים בהו על פי בה פי ה' אמר מרים נמי בנשיקה דאתיא שם שם ממשה ומפני מה נאמר בה על פי ה' שגנאי הדבר לומר Our Rabbis taught: Six there over whom the Angel of Death had no dominion, namely, Abraham, Isaac and Moses, and Abraham, and Jacob we know because it is written in connection with them, in all, of all, Moses, Aaron and Miriam because it is written connection with them [that died] By the mouth of Lord. the words the of Lord’ are not in connection with [the death of] Miriam? — R. Eleazar said: Miriam also died by a kiss, we learn use of word [in both with her with that of Moses. And why said of her that [she died] by the of the — Because such an expression would disrespectful. (Soncino translation) While the Talmud does not what the disrespect is, there are parallel versions of this teaching in other Midrashic sources. of them, it explicitly that the disrespect to the when of a Yalkut Shimoni Parshat Chayei Sarah ששה לא שלט בהן מלאך המות יצחק ויעקב דכתיב בהו בכל מכל כל משה אהר�
רן
  ומרים אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה אהרן ומרים דכתיב בהו
  על פי ה' והא מרים לא כתיב בה על פי ה' אמר ר"א מרים נמי בנשיקה מתה
  דאתיא שם שם ממשה ומפני מה לא נאמר בה על פי ה' שגנאי הדבר לומר
Our Rabbis taught: Six there weRe over whom The AnGel Of DEaTh haD no
  dOminion, namely, ABRahaM, Isaac and Jacob, Moses, AarOn and miRIam.
  ABRaHam, IsAac and JACoB WE knOw BeCauSe IT iS writTen In conneCtion
  with tHem, In All, of all, all; MOSeS, Aaron and MIriAm because it iS
  wrItten iN cOnnECtion WitH them [That thEY died] BY the mouth Of THe
  Lord. bUt the woRDS ‘bY the Month of the Lord’ are NOt USed in
  connectioN with [tHe DEaTH Of] MIriAm? — R. Eleazar SaId: MirIAm also
  dIEd BY A KisS, As we learn from The use of the WOrd ‘There’ [iN
  cOnnECtion bOth wiTh HEr dEath] and with That Of Moses. AnD why is IT
  not saiD Of her thAt [she dIed] By tHe moNTh1 Of The loRD? — BeCAuSe
  sUCh aN expressIoN wOuld bE disRESPEctfUl. (SOnciNo traNslation)

While The talmUD doEs not State What ThE disrEspect Is, theRe Are parallel versIons Of this teaChiNg In oThEr MidRAshic sOurCes. in one of Them, it eXPliCiTLY StAtes that the disrespEcT IS tO use the tErm wheN SpEaKIng of a woMaN:
YaLkut sHImoni parsHAt chayei SaRah

ששה לא שלט בהן מלאך המות אברהם יצחק ויעקב דכתיב בהו בכל מכל כל משה
  אהר�
רן
  ומרים אברהם יצחק ויעק ב דכתיב בה ו בכל  מכ ל כ למשהאהרן  ומרים דכתיב ב ה ו
 על פי ה' והא מרים לא כ תיב ב הע ל פי ה'  אמרר"א מרי ם  נ מ י  בנ שי קה  מת ה ד אתיאשםשם ממשה  ומפני מהלאנא מר בה על פיה 'שגנאי הדבר  לו מר
Our Rabbi s t aught:  S ixt herewer e ove r whom the An gel of De at h  had n o 
  domi n i on , na mely, Abraham, Is a ac and Jacob, Mos es, Aa ro n  a n d  Mi ria m.
  Abrah am , Isa a c and J a co b w e k n ow because it  is written inconnec ti on withthem,  i n  al l, of all,all;  Moses, A aron a n d Miria m  becaus e it i s
 wr itte n  i ncon ne c tio n  w ith the m [thatth ey  died ] By t h e  mou thof t he
 Lord. But the  wo rds‘ bythe m onthof t he  Lord ’ arenot u se d in
  connecti on w ith [thedea th  of ]Miria m ? — R.  El eaz ar said : Miria m  al so di ed by a kiss, as w el e ar n from t he use of  t h e word ‘ th ere ’ [i n   con nect i on  both wi th her de at h] andwi th tha tofMos es. A n d wh y is i t
  notsaido f her that [sh e  died] by the mo n t h1 of t heLord? — Bec ause   su ch a n  e xpr e ssion  woul db ed isrespectful. (Sonc in o tran slati on)

While th e Talmud d o e s  not sta te w h at the disrespect  is,there arep arallelversi ons of t his teach i n g in oth erMid ras hic s ou rces. In oneo f  the m,  it exp lic itly st ate s t hat  th edisrespec t is tous eth eter m whe n  speakin gofawom an:
Y a lkut S himon i Pa rs ha t  Ch ayei Sa r ah ששהלא  ש לט ב הןמל אך המ ות א ב רהם  יצחק ו יעקב דכתי ב ב ה ו בכ למכ ל כל מש ה
  אהר�
רן
 _ומרים אברהם_יצחק ויעקב דכתיב בהו_בכל מכל_כל_משה אהרן_ומרים_דכתיב בהו
 _על פי ה'_והא מרים לא כתיב_בה על פי_ה'_אמר ר"א מרים נמי בנשיקה מתה
  דאתיא שם שם ממשה ומפני מה לא_נאמר_בה על_פי_ה'_שגנאי הדבר לומר
Our Rabbis taught:_Six there were over whom_the Angel_of Death had no
  dominion, namely, Abraham,_Isaac_and Jacob, Moses,_Aaron and Miriam.
  Abraham, Isaac and Jacob we_know because it is written in_connection
  with_them,_in_all, of all, all;_Moses, Aaron and Miriam because it_is
  written in connection with_them [that they died] By the mouth_of the
  Lord. But the_words ‘by the month of_the Lord’_are not used in
 _connection with [the_death of]_Miriam? — R._Eleazar said: Miriam also
  died_by a kiss,_as we learn from the use_of_the word ‘there’_[in
__connection both_with her death]_and_with that_of_Moses. And why is it
 _not_said of her that [she died] by_the month1 of the_Lord?_— Because
  such_an expression would be disrespectful._(Soncino translation)

While the Talmud does not_state what_the disrespect_is, there are parallel versions of this teaching in other Midrashic_sources. In one of them, it_explicitly states that the_disrespect is_to_use the term_when_speaking of_a woman:
Yalkut Shimoni Parshat Chayei Sarah

ששה לא_שלט בהן_מלאך המות אברהם יצחק ויעקב דכתיב_בהו בכל מכל כל_משה
_ אהר�