Two living compounds. (1) 颟顸 — 'muddle-headed / sloppy / careless in handling things', a classic Lu Xun-era vocabulary word for bureaucratic incompetence. (2) 顸实 — dialect / colloquial 'thick and solid' (of a stick, rope, neck). Northern speech only.
register
Northern dialectal and literary. 颟顸 is used in essays and political satire ('our bureaucracy is 颟顸'); the 顸实 sense is regional and informal.
Right 页 (Kangxi #181, head) — the head-radical anchors the original sense: a thick or muddle 'head' = stout / dull-witted. Same radical drives 颟 (its partner in 颟顸), 颜, 顽, 顶.
