Possible etymology

English

English word possible comes from Latin sum ((copulative) I am, exist, have (with dative).), Latin -ius, Proto-Indo-European *pótis (Husband. Master, ruler.)

Detailed word origin of possible

Dictionary entry Language Definition
sum Latin (lat) (copulative) I am, exist, have (with dative).
-ius Latin (lat) Genitive suffix for some irregular pronouns. Forming adjectives from nouns.
*pótis Proto-Indo-European (ine) Husband. Master, ruler.
*potis Proto-Italic (itc-pro)
potis Latin (lat) Able, capable, possible.
possum Latin (lat) I am able, can.
possibilis Latin (lat) Possible, that may exist, that may be done.
possible English (en) (colloquial, rare) A possible choice, notably someone being considered for a position.. (rare) A particular event that may happen.. A possible one. (comparable) Capable of being done or achieved; feasible.. (usually, not comparable) Able but not certain to happen; neither inevitable nor impossible.. Apparently valid, likely, plausible.. Being considered, e.g. for a position.