Assuming $G=(V(G),E(G))$ is a graph what does $\Delta(G)$ mean?

Question

Perhaps someone is kind enough to explain to me the meaning of this mathematical symbol, that I found in Discrete Mathematics (Matroid Theory)?

Let $G=(V(G),E(G))$ be a graph. What does

$$\Delta(G)$$

mean? From the context I can determine, that $\Delta(G)$ computes an integer $k\in\mathbb{N}$. But I don't know for what $k$ stands.

The exercise is: Let $k\in\mathbb{N}$ and $G$ be a graph. Define $$\mathcal{F}_{G}:=\{F\subset E(G): \Delta((V(G),F))\leq k\}$$ etc.

Answer 1

Probably the maximum degree.