Sniffling or sniffing; in a state of sniffling or having a runny nose.
From 'a-' plus 'sniffle,' where 'sniffle' is a diminutive or onomatopoetic form from 'sniff,' which comes from Middle Dutch or Low German. The '-le' suffix makes it iterative (repeated sniffing).
This is such a specifically miserable word—'the child was asniffle'—it captures that particular state of a cold or crying better than any modern word, and it's another example of how onomatopoeia thrived in the 'a-' prefix era.
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