Adsto/adstare/adstiti - to stand near, stand up
Intransitive verb of the first declension. The perfect tense doesn't form in the usual way that would be expected of the first declension, but there is 'reduplication' of the consonant.
It is formed from the preposition ad (towards) and the verb sto (I stand).
The original verb sto and its parts have many links to English - stand, status, statue, ...
Though adsto conveys the sense of 'standing near' or' standing up', rather than just 'standing', in many cases of use it seems that either adsto or sto could have been used. What should be avoided is using adsto for 'standing afar off.'