Sum and Size up

Sum verb - To combine (numbers) into a single sum.

Size up and sum are semantically related In some cases you can use "Size up" instead a verb "Sum".

Size up verb - Look at critically or searchingly, or in minute detail.

Sum and size up are semantically related in estimate topic. Sometimes you can use "Sum" instead a verb "Size up", if it concerns topics such as calculate, guess, summarize, compute or estimate amount.