It could mean a wide variety of things. As a word, it could mean 'doer, haver, owner, etc' when combined in a combination word.
Other than that it's an inflection (te-form*) of the verb 'suru', which means in general 'to do, to make happen, to play, etc' and as an auxiliary verb attaches to nouns to create verb forms of the same meaning the noun conveys.
*: Te-form is one of many variations of inflections that occur to a word (in this case a verb) in Japanese, which suggests continuity (one of the usages of te-form is in 'continuous forms of verbs' like: shite iru : doing) and linking of an action to the next. Its usage is similar to how we make a 'clause' or use 'conjunctions' in English.
i.e :
'Baka (stpid, idiot)' + 'ni (particle)' + suru = bakani suru (make a fool of , to make fun of)
Usage:
Bokura WA aitsu wo bakaini shite shikkari warattanda.
(We made fun of him and laughed wholeheartedly)
"What are you doing?"
it means tactful
Tomorrow comes and we have to say goodbye
"Rikai shite inai" is a Japanese phrase that means "I don't understand" in English. It's commonly used when someone is struggling to grasp a concept or idea.
"I am studying the Japanese language." Watashi wa = I am Nihongo = Japanese (language) Obenkyou = Study Shiteimasu = I am doing (the aforementioned verb)
'Annai shimasu/shite ageyou.'
You may say 'shikkari shite (kudasai.)'
ogenki desuka
'Mada benkyou shite imasu ka.'
Uta wo ai shite iru
Shinrai shite i nai hito
Kon'ban tanoshiku shite