This term can be used in reference to 3 main things:
Inflorescence: 1) Flowering part of a plant 2) A group or cluster of flowers on an axis that are not separated by branching or leaves. 3) The arrangement of flowers within a cluster. This can be in the form of many shapes, patterns, and sizes.
*Practice note: Here are a few photo examples of each usage of the word.
1) Single inflorescence:
2) Inflorescence of multiple flowers: general term
3) Inflorescence arrangement: A few of the MANY