stick-in-the-mud has definitions from the field of work
1
[ adjective ] (used pejoratively) out of fashion; old fashioned

Examples

"moss-grown ideas about family life"

Related terms

nonmodern unfashionable

2
[ adjective ] (used pejoratively) out of fashion; old fashioned

Examples

"moss-grown ideas about family life"

Related terms

unfashionable

3
[ noun ] (work) someone who moves slowly

Examples

"in England they call a slowpoke a slowcoach"

Related terms

dawdler slog

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