What is the meaning of O-?

A blood type that has no antigens. It lacks the A, B and Rh factors on the blood cells. It is the universal donor for blood and can give blood to any blood type, but can only receive O- blood.

ortho-

combining form of ogi (“bread”)

Separable verb prefix that indicates a direction, goal, destination and a contact made therein.

noun prefix

marks the second-person singular subject on a verb

Forms nouns from some verbs; verbal noun modifier; ‘place where...’.

noun prefix

her

Second-person singular relative concord.

Class 1 relative concord.

Class 3 relative concord.

A prefix denoting the third person

appears in front of some verbs meaning: to make something behave in a certain way, en-, be-, make

around

prefix indicating a perfective verb

noun prefix

noun prefix

Forms perfective verbs with the following meanings:

1. (no change in meaning)

   (no change in meaning)

   around, past, avoiding

   to stay, to remain

   Second-person singular relative concord.

   Class 1 relative concord.

   Class 3 relative concord.

   First person singular subject + third person duoplural object.

   Second person singular subject + third person singular object.

   third-person singular clitic, he

   you; 2nd person singular subject concord

   allomorph of öt- (detransitivizing prefix)

   allomorph of ö- (second-person prefix) used for stems that begin with a consonant and have a first vowel o or u

   With following vowel lengthened if in an unreduced open syllable.

   The contracted form of the -a of association particle combined with the ku- prefix of the infinitive when deriving adjectives from verbs.

   Class 2 verbal modifier prefix, contraction of "aku-" or "a ku-".

   Class 6 verbal modifier, contraction of "aku-" or "a ku-".

   around, all around

   a complete action, a perfective verb

   something else

   Rōmaji transcription of お

   ab-; away, off from

   prefix indicating a perfective verb

   affects verb meaning in various ways

   appears in front of some verbs meaning: to make something behave in a certain way, en-, be-, make

   around

   down

   Added to adjectives to yield their opposites; un-

   Added to nouns to mean lack or being without

   denotes future tense in verbs and adverbs

   soft mutation of go-

   Second-person singular relative concord.

   Class 1 relative concord.

   Class 3 relative concord.

   Second-person singular relative concord.

   Class 1 relative concord.

   Class 2a noun prefix.

   Class 3 relative concord.

   Source: wiktionary.org