If you use the plus symbol ' ', it means the same as the word 'and'.
如果你用加号“＋”，它和“and”的意思是一样的。
可汗学院公开课：英语语法
We usually says it looks like this little plus symbol.
我们通常说它看起来像这个小加号。
英语百科
Plus and minus signs
The plus and minus signs (+ and −) are mathematical symbols used to represent the notions of positive and negative as well as the operations of addition and subtraction. Their use has been extended to many other meanings, more or less analogous. Plus and minus are Latin terms meaning "more" and "less", respectively.