occasion, side, edge, verge, dangerous, adventurous, indecent, time, when
際 centers on the boundary or meeting point between two things: a physical edge or verge, or a point in time when something happens. The meanings 'dangerous', 'adventurous', and 'indecent' are less common and may be specialized or archaic uses.
際 combines ⻖ (mound, hill, boundary) with 祭 (ritual, festival). The original idea likely involved a boundary or meeting place marked by a ritual, extending to edges and occasions.
Picture a hillside (⻖) where a festival (祭) is held at the edge of town. The boundary between the hill and the festival grounds is the 'verge' or 'occasion' where people gather.
For サイ, imagine a sigh (サイ) of relief when you finally reach the edge of a long journey. The sigh echoes the reading サイ as you stand at the boundary.
reality; actuality; truth; fact; actual conditions
occasion; time; circumstances; (in) case (of); when
international
company; friendship; association; society; acquaintance
to be prominent; to be conspicuous; to stand out; to be outstanding; to be remarkable; to be striking; to be notable
the point just before ...; the point of (doing); the verge (of); the eve (of)
at the window; by the window; next to the window
skill; ability; dexterity
limits; end; bounds
brink; verge; critical moment; crucial moment
water's edge; waterside; shore
interdisciplinary
edge of the ring
on the occasion of; at the time of; when; during
entertainment expenses
internationally minded person; cosmopolitan; cosmopolite; citizen of the world
internationalization; internationalisation
Japan International Cooperation Agency (1974); JICA
international law; law of nations
international; worldwide; cross-border; cosmopolitan
United Nations; UN
in fact; as a matter of fact; actually; in reality; to tell the truth
efficiently; skillfully; adeptly; adroitly; deftly
paid dating (esp. with an underage girl; oft. involving selling of sex); compensated dating
meeting; facing; confronting