four: the cardinal number 4
This is simply the number four, used to count people, objects, and units of time. It works exactly as the English word does: four men carrying a paralyzed man (Mark 2:3), four days in the tomb (John 11:17), four soldiers dividing clothing (John 19:23), four anchors dropped from a ship (Acts 27:29). There is nothing hidden in the word itself; it counts what it counts.
Where four becomes striking is not in its dictionary meaning but in how often the Bible uses it to picture wholeness across the whole world. Four winds blow from four directions and four corners of the earth, a way of saying "from everywhere" (Matthew 24:31, Mark 13:27, Revelation 7:1). Four angels stand at the edges of the earth, and four messengers gather the chosen from end to end.
This whole-world sense saturates Revelation, which uses four more than any other book. The four living creatures around God's throne, echoing the four faces of the cherubim Ezekiel saw, represent all of creation worshiping its Maker. The pattern does not change the meaning of the number; four still means four. It simply shows that biblical writers loved to let the count itself carry a picture of completeness reaching in every direction.