1. ultra- a prefix occurring orig. in loanwords from Latin, with the basic meaning “on the far side of, beyond.” In relation to the base to which it is prefixed, ultra- has the senses “located beyond, on the far side of” (ultramontane; ultraviolet), “carrying to the furthest degree possible, on the fringe of” (ultraleft; ultramodern), “extremely” (ultralight); nouns to which it is added denote objects, properties, etc., that surpass customary norms, or instruments designed to produce or deal with such things (ultramicroscope; ultrasound; ultrastructure).
Etymology: (< L ultrā (adv. and prep.) on the far side (of), beyond)
1. ultra- extremely an ultra-conservative group; ultra-low power electrical devices
Definition of 'ultra-'
Webster Dictionary
1. (adj)ultra- a prefix from the Latin ultra beyond (see Ulterior), having in composition the signification beyond, on the other side, chiefly when joined with words expressing relations of place; as, ultramarine, ultramontane, ultramundane, ultratropical, etc. In other relations it has the sense of excessively, exceedingly, beyond what is common, natural, right, or proper; as, ultraconservative; ultrademocratic, ultradespotic, ultraliberal, ultraradical, etc
Definitions of ultra- 
Afrikaans: ultra
Arabic: فَوق، ما وَراء
Bulgarian: ултра-
Brazilian: ultra
Czech: ultra-
German: ultra...
Danish: ultra-
Greek: υπερ- (ως β΄ συνθ.)
Spanish: ultra
Estonian: ultra-
Farsi: افراطی
Finnish: ultra-
French: ultra-... ultraviolet
Hebrew: עַל-, אוּלטרָה-
Hindi: चरम
Croatian: ultra
Hungarian: ultra-
Indonesian: ultra
Icelandic: útfjólublár
Italian: ultra-
Japanese: 超[]－
Korean: 초(超)…, 한외(限外)…의 뜻
Lithuanian: ultra-
Latvian: ultra-
Malay: ultra
Dutch: ultra-
Norwegian: ultra-
Polish: po(nad)
Persian: افراطی
Pashto: بی حد
Portuguese: ultra
Romanian: ultra-
Russian: ультра-
Slovak: ultra-
Slovenian: ultra-
Serbian: ultra
Swedish: ultra-
Thai: เกิน
Turkish: ...ötesi
Taiwanese: (前綴)超，在...之外
Ukrainian: над-, ультра-
Urdu: ماورا
Vietnamese: siêu cực
Chinese: （前缀）超….（表示`极端，过度`之义）
