This happens whenever more than ten people want to read from their work, as even ten minutes for reading and five for discussion can add up to one long evening and a certain dulling of the powers of concentration once the second hour has passed.
The loss of the original keenness (dressed keenness) of the tool cutting edge and the outer comers in the process of cutting is called dulling, its result is called wear.
There also seems to be a "dulling" of the power to perceive an odour which is a consequence of constant exposure to that odour.
The major downside of soap, however, was that it left hair coated with a discouraging, dulling film.
The orgasm and the heady feeling of wholeness rushed over his senses, dulling the panic and fear.