vessels, counter for ships, fish, birds, arrows, one of a pair
隻 centers on the idea of one item from a pair or set: a single vessel, bird, fish, or arrow counted individually. The counter sense is a natural extension of this one-of-a-pair concept.
隻 combines 隹 (a short-tailed bird) with 又 (a hand), originally depicting a hand holding a single bird, hence the meaning 'one of a pair'.
A hand (又) holding a single bird (隹) — just one from a pair. This image helps remember the core idea of a single item from a set.
For セキ, imagine a single bird sitting on a hand, and the bird says 'seki' (like a chirp). The sound 'seki' cues セキ while the hand holds one bird.
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counter for ships
one eye
every single word and phrase; each and every word
one boat; one ship
discerning eye; critical eye
several (boats)
few words; single phrase
(not even) a few words
a few words
a glimpse of an object's outlines
one hand; one arm
the sound of one hand clapping (a classic Zen koan)
the sound of one hand clapping (a classic Zen koan)
one-legged
one arm
just a few words