I was taught that shaddah means the letter is doubled; the first "letter is sakin, the second has it's particular..

BarakAllaahu fikum for your informative and enlightening answer to my last question.  This question is related in a way and concerns a letter with fat-hah followed by a yaa with shaddah. 

I was taught that shaddah means the letter is doubled; the first "letter is sakin, the second has it's particular vowel mark (fat-hah, dhammah, kesrah), (well, except when the letter with sheddah is stopped at...) for example in Allaah Ta'ala's Glorious Names "AL-HAYYu-AL-QAYYUM -  Al-HAYY is read as HAA with fat-hah, YAA sekoon, YAA with dhammeh and Qayyum is read as QAF with fat-hah, YAA sekoon, YAA with dhammeh.  Is this correct?  Do we have then the same sound as words that have MED LEEN i.e KHAIR or `ALAYHIM or BAYNA?  Is it the same type of sound but technically it should not be referred to as med leen?  I ask because I help a sister with Tajweed  on Ayaat-ul-Kursi and I ask her to show me different examples of certain Tajweed rules in the Ayaat and I explained this to her as MED LEEN.  God forgive me if I am wrong and speaking about this without the sure knowledge.  insha'Allaah can you clarify for me so that I can point out my mistake to the sister.  Allaah yezeedik khayr.

Answer

Wa alaikum assalaam wa rahmatullahi wa barakatuh.

The shaddah does indeed mean doubled, the first saakin the second with the vowel on the shaddah, but the rules that apply to the letter when influenced by the letter before may change with a shaddah.  In the case of the wordswe have a  with a shaddah, preceded by a fat-hah. This is not   is when there is a   or  saakinah preceded by a fat-hah and followed by only one letter which is voweled, and we are stopping on that word with a temporary sukoon, such as last word in the following aayah:  is lengthened two, four, or six vowel counts.  Please see the following link for more details: http://www.abouttajweed.com/al-mudood_part_7_medd_'aaridh_leen.htm ; you will need to scroll down half the page to read about  .

What you most likely meant is that you suggested to the sister that it was a leen letter. A leen letter is when there is a  or  saakinah preceded by a fat-hah and not followed by a sukoon.  The leen letter is lengthened less than two vowel counts but more than one vowel count.

What we have in the words is a need for a , or accent to make the shaddah on the  clear and to prevent us from lengthening the fat-hah on the letter preceding the .  We do not lengthen these words and similar types of words the normal length of a leen letter, if we did, the shaddah would not be clear.  Please see the following link for a detailed explanation of the  and its different conditions: http://www.abouttajweed.com/new_page_7.htm The second case (in the first of the two links on the accent or ) explains the same conditions as are present in the words

Al-hamdu lillah that you have such a strong desire to present correct knowledge to the sisters you are helping, may Allah increase you in beneficial knowledge.

Wa assalaam alaikum.