Boyd’s Bible Dictionary:

(people’s victor). The Pharisee ruler and timid convert who assisted at Christ’s sepulture (John 3:1-10; 7:45-52; 19:39-42).

Concise Bible Dictionary:

One of the Pharisees and a teacher in Israel. He came to the Lord by night for instruction, and was greatly astonished to find that, instead of instruction, he needed to be born again. See NEW BIRTH. To this the Lord added that the Son of Man must be lifted up: sin must be condemned, and the Son of God be given in love, in order that whosoever believeth in Him should have everlasting life: that is, heavenly blessings in new creation. Nicodemus afterward grew bolder, and suggested in the council that the Lord ought to be heard, and His acts examined before He was condemned. The last we read of Nicodemus is that after the crucifixion he brought about a hundred pounds’ weight of myrrh and aloes to embalm the Lord’s body (John 3:1-9; John 7:50; John 19:39). This last act was a tacit acknowledgment of his attachment to the One to whom he had come for instruction, but who had spoken to him of God’s love, and of heavenly blessings through the Son of Man lifted up, and whom he had attempted to defend in the council.

Strong’s Dictionary of Greek Words:

from 3534 and 1218; victorious among his people; Nicodemus, an Israelite
KJV Usage:

Jackson’s Dictionary of Scripture Proper Names:

conqueror of the populace

Potts’ Bible Proper Names:

Conqueror of the people; victorious among his people:―a Pharisee ruler, John 3:1. {Victor populi}