(literary) spring dream / (literary, figuratively) short-lived occurrence; brief moment of joy; transient joy

Largehead hairtail, Trichiurus lepturus, a member of the cutlassfish family

a pit trap or snare / a hole in the top of a box or other container for dropping things in / (figuratively) a deliberate ploy to deceive someone into a bad situation: a deliberate pitfall

brief moment