al-Salāmu ‘alaykum wa rahmatullāh,
The last post on Ishtiqaaq saw how the scholars of Arabic agreed that words derived from the same [usually triliteral] root share a common meaning among them.
A number of great classical scholars of Arabic such as al-Khalil ibn Ahmad al-Faraaheedee, Abu ‘Ali al-Faarisi, and his student Ibn Jinni, understood this idea even further and suggested the notion of al-Ishtiqaaq al-Kabeer  (‘the Greater Derivation’) wherein they noticed that three letters within a root – regardless of the order in which the letters are arranged – can also be said to share in a common meaning. For example, the roots ب-ر-ج and ب-ج-ر and ج-ب-ر and ج-ر-ب and ر-ج-ب and ر-ب-ج, along with all their derivations, would all share in one central theme or meaning, due to their being composed of the same three letters.
In his book al-Khasaa’is, Ibn Jinni elucidated on this phenomenon, providing detailed descrptions and examples. To continue with the same root mentioned above, Ibn Jinni says that these three letters combined connote the meaning of strength and power, as in:
1. From the root ج-ب-ر:
jabartu al-faqeer جبرت الفقير to mean ‘I restored a man from a state of poverty to wealth.’
A King is referred to as the jabar جبر due to the strength and power he holds.
2. From the root ج-ر-ب:
One says about a man that he is mujarrab مُجَرَّب if he has gone through a trial, and strengthened by his experiences.
A jiraab جِراب refers to a case that protects something else (e.g. travelling provisions, or a sword) because when something is protected it is strengthened.
3. From the root ب-ج-ر:
A bujr بحر affair is one which is extremely terrible or momentous.
The adjective bajeer بجير is used to refer to something in abundant, copious amounts.
4. From the root ب-ر-ج:
A burj بُرج refers to a tower or fortress, due to being self-sufficient in its provisions, and power to protect those inside and within.
Baraj بَرَج is used to describe an eye in which the black and white parts are extremely strong and pure in their colour.
5. From the root ر-ج-ب:
One says rajibtu al-rajula رجِبتُ الرجلَ if they revere a man, honour him, venerate him, and regard him with awe.
The seventh month of the Islamic calendar is known as Rajab رجب because the Arabs held this month in such strong esteem that they forbade fighting in this month.
6. From the root ر-ب-ج:
The rubaajee رُباجيُّ is a man who is proud and boastful of his actions more than they deserve.
 While Ibn Jinni referred to this phenomenon as al-Ishtiqaaq al-Akbar (in the superlative form), it is usually known as al-Ishtiqaaq al-Kabeer (in the elative form).
 Note that they acknowledged it could not and would not apply to every root, just as the regular ishtiqaaq
would not apply to every root.