Full Idea
The meaning of a word (such as 'felony') is the thing conceived; and that meaning is the conception affixed to it by those who best understand the language.
Gist of Idea
A word's meaning is the thing conceived, as fixed by linguistic experts
Source
Thomas Reid (Essays on Intellectual Powers 4: Conception [1785], 1)
Book Reference
Reid,Thomas: 'Inquiry and Essays', ed/tr. Beanblossom /K.Lehrer [Hackett 1983], p.223
A Reaction
He means legal experts. This is precisely that same as Putnam's account of the meaning of 'elm tree'. His discussion here of reference is the earliest I have encountered, and it is good common sense (for which Reid is famous).
Related Idea
Idea 2338 Reference (say to 'elms') is a social phenomenon which we can leave to experts [Putnam]