Reverse Dictionary: POSSIBLE

ADJECTIVES
CASEABLE able or liable to happen, possible → c1565 Sc. obs.
ON possible, feasible, worthy of an attempt → 1935 UK sl.

ADVERBS
ABLES perhaps, possibly → 1883 Sc.
ABLINGS ► ABLINS in a manner that is able to be; possibly, perhaps → 1597
BEHAPPEN perhaps, possibly → 1898 Eng. dial. (Bk.)
BELIKE likely, in all likelihood, probably, maybe; not unlikely, perhaps, possibly → a1533
BELIKELY likely, in all likelihood, probably; not unlikely, perhaps, possibly → a1552 obs. exc. Eng. dial.
HAPPEN ► HAPPENS perhaps, possibly, maybe → 1790 N. Eng. dial.
MAPPEN perhaps, possibly → 1848 Eng. dial.
MAYHAP ► MAYHAPS perhaps, possibly → 1794 Sc. & Eng. dial.
MAYHAPPEN perhaps, possibly → 1848 Eng. dial.
PERHAPPEN perhaps, possibly → 1578 Sc. & Eng. dial., obs.
YEABLES YIBBLES possibly, maybe, perhaps → 1868 Sc.

NOUNS
DANGER a chance, a possibility; a likelihood → 1920s sl.

PHRASES
CAN DO it is possible, it is within my power → 20C sl.
SNOWBALL’S CHANCE IN HELL, A no possibility at all → 1934

VERBS
DRIVE THE NAIL WHERE IT WILL GO to only attempt the possible → 1655  Amer. dial.
POSSIBILITATE to make possible → 1829