[RPG] Does a character have line of sight on enemies directly behind them

dnd-5eline-of-sightspellstargeting

When reading the wording for the Word of Radiance cantrip, it says:

Each creature of your choice that you can see must pass a Constitution save or take 1d6 radiant damage.

Let's say that my cleric is standing in an open area with enemies within 5 feet on all sides. How would I be able to hit enemies behind me at the point of casting? The whole point of the spell is to hit everyone around you, and it is purposefully not a cone, but it seems like there is no way to have line of sight 360 degrees around you.

The only [mainly flavor] explanation is that it works because the character can spin around 360 degrees during the casting time to "see" the targets behind them.

5e lacks official flanking rules, so is there any clarification on the interaction between line of sight and positioning in cases like this?

Best Answer

The rules assume that facing direction doesn't matter.

Therefore they routinely use "creature you can see" to mean "creature you could see, if you were to look in that direction". For example, opportunity attacks trigger when "a creature you can see" moves out of your reach.

If the spell was intended to operate only in the direction the caster is looking at the moment, it would be a cone. Since it's not, we should assume it radiates in all directions.