noun, noun or participle which takes 'suru'
put heads together and confer; go into a huddle (over)
A yojijukugo meaning to gather and discuss something intently, often with heads close together. Used in formal or literary contexts.
委員会は鳩首凝議して対策を練った。
The committee put their heads together and worked out a plan.
協議 is a general term for discussion or consultation, while 鳩首凝議 specifically implies an intense, close-knit huddle-like discussion.
A yojijukugo combining 鳩首 (gathering like doves, heads together) and 凝議 (intense discussion). The exact historical derivation is uncertain.