Qur'aan Corpus-Surraiya Encyclopedia of Arabic of Grand Qur'aan;Root: ل غ و

Beginning is with Allah's personal name Ar'Reh'maan Who is The Fountain of Infinite Mercy.

Root: ل غ و

Words from this Root in the Grand Qur'aan:

a) Total occurrences: 11

b) No of constructions: 7

لغو (مقاييس اللغة)

اللام والغين والحرف المعتل أصلانِ صحيحان، أحدهما يدلُّ على الشَّيءِ لا يُعتدُّ به، والآخَر على اللَّهَج بالشَّيء.

That it leads to the perception of something which is inappreciable, inconsiderable; and secondly to attach to - be very fond of, mention continually, repetitively talk of or about something.

Its usage in the Grand Qur'aan is in the perception of frivolous, vain, futile, absurd, palaver, empty talk void of substance; myths, gossips, and thoughtless utterances like catch phrases.

Allah the Exalted will not hold you people accountable for your superfluous-artificially speaking promissory chatters in sworn circumstances [since they are utterances of mouth of no import-consideration].
But be mindful that Allah the Exalted will hold you responsible and accountable for those vows, pledges-promises which your hearts have earned-arrived at. [well thought, determined, intentional]
Be cognizant, Allah the Exalted is eternally imperturbably over looking-forgiver [of unintentional faults/wrong doings] [2:225]

: It has nothing at all to do with the concept of "ignorance" contra. of the Knowledge. It is also done with the objective to down the others talk, roping away—limiting the efficacy of others talk. Obviously this cannot be done by "ignorant-one who lacks knowledge", rather it is in itself a skill.

Know it: those- ruling elite who refused to accept the Book had advised aristocrats:
"You people should not attentively hear this Qur'aan.
Instead, you are instructed to devise and spread conjectures- palavers about it for roping away- limiting its efficacy- rendering it nugatory.
This strategy might enable you people retain the dominating authority." [41:26]

The majority of aristocracy and their coterie scholars use their Logical Brain-Frontal Lobe of cerebral cortex associated with higher function of thought and action. It is associated with reasoning, planning, movement, problem solving, emotion's control, and parts of speech [Broca's area]. They use this faculty to plan deceptive and falsified tactics to exercise and perpetually retain their authority and dominance over general public whom they consider in their privacies as: the vilest-riffraff of society.