This is the 876th most frequent Catalan word.
sumar
To add.
In this sentence, 'sumar' is used in its mathematical sense, meaning 'to add' or 'to calculate a total.'
Hem de sumar tots els ingressos del mes.
We need to add up all the income for the month.
In this example, 'sumar' is reflexive and means 'to join' or 'to become part of.'
Vull sumar-me a la causa.
I want to join the cause.
Here, 'sumar' conveys the figurative meaning of 'to join together' or 'to combine resources or efforts.'