Fakhir: This is word is a combination of three alphabets in Urdu
(Fa + Qa + Ra) . It is actually an abbreviation stands for
Fa -- Fakhakashi
Qa -- Qiyadath
Ra -- Riyaz-ul-Quran
Tassavuf: This is word is a combination of Four alphabets in Urdu
(Ta+sa+Va+fa). It is actually an abbreviation stands for
Ta -- Tauba
Sa -- Sadgi
Va -- Vilayath
Fa -- Fanafilla
Peer: The master/teacher/guide/ancestor who teaches/guides the students(Mureed) in the path of Allah -- The Almighty.
Mureed: Seeker/student who learns the education from his/her Peer in the Path of Allah - The Almighty.
Sajjada: The person who is responsible for taking care of all people in Silsila and guiding them in the right direction, this post is available only in shrines (dargah). A sajjada can be a peer but vice versa may or may not be true. This person is also responsible for all activities/customs to be carried out in the shrine through out the year.
Jaanasheeni: It is like a will which states the name of the person responsible for the property of the FAKHIR after him. Usually this will go from Peer/Fakhir/Sajjada to his elder son. This property cannot be shared among other childrens like money/land is shared.