1.
oar (for rowing a boat)
A long pole with a flat blade at one end, used to row a boat by pulling against the water. From English 'oar'.
2.
all; entirely (used as prefix or in compounds)
From English 'all'. Used as a prefix in compounds like オールラウンド (all-around), and casually to mean 'staying out / staying up all night' as in オールする.
Loanword that covers two unrelated English sources: 'oar' and 'all'. Context makes the meaning clear.
SENSE 1 (oar):
SENSE 2 (all):
- オールラウンド: all-around
- オールスター: all-star
- オールマイティ: almighty; versatile
- オールする: to stay out / stay up all night (casual, especially among students)