Meaning of Periodic in dictionary was found to be "appearing or occurring at intervals".
Purpose of Reason for naming the Periodic Table:
The elements is periodic table have been found of having same iso-electronic properties and the major periodicities found are of two, eight and eighteen respectively.
Examples:
First Group elements tends to loose only one electron to form M⁺ cation. Starting from Lithium with atomic number 3, secondly sodium which has atomic number 11. When 3 (lithium) is subtracted from 11 (sodium) (i.e. 11-3=8) eight is attained. Same when 11 (sodium) is subtracted from 19 (Potassium), again 8 is obtained. Going downwards the group the number of 18 is obtained i.e. Rubidium (37-19=18), Cesium (55-37=18).
Seventh Group elements tends to gain only one electron to form X⁻ anion. Starting from Fluorine with atomic number 9, secondly Chlorine which has atomic number 17. When 9 (Fluorine) is subtracted from 17 (Chlorine) (i.e. 17-9=8) eight is attained. Same when 17 (Chlorine) is subtracted from 35 (Bromine), 18 is obtained. Going downwards the group the number of 18 is obtained i.e. Iodine (53-35=18).
Conclusion:
Hence, we can conclude that Periodic Table is designed in such a way that after a particular interval the chemical and physical properties of elements repeats. Therefore, it can help in understanding the nature of elements without going into experimental experiments.