What is the difference between the linguistic and technical meanings, and how did scholars technically specify plucking (namṣ) to the eyebrows, even though linguistically it refers to removing facial hair?

The difference between the linguistic and technical meanings is that the linguistic meaning represents the sense in which Arabs used the word, while the technical meaning is the sense agreed upon by the specialists of a particular discipline for that word.

For example: - Salat (Prayer): Linguistically, it means supplication (du'a). Technically, it is an act of worship consisting of specific words and actions, beginning with takbir (pronouncing 'Allahu Akbar') and ending with taslim (saying 'As-salamu alaykum wa rahmatullah'). - Zakat (Alms): Linguistically, it means growth or purification. Technically, it is a well-known act of worship involving the taking of specific wealth, under specific conditions, from a particular person. - Sunnah: Linguistically, it means method or way. It has several technical applications depending on the discipline.

Regarding scholars restricting the meaning of namṣ to eyebrows, please refer to Fatwa No. 113767.