Thick

Thick as in a thick voice or to say something thickly is to speak in a hoarse, guttural way, sometimes choked with emotion, and dates from the 1500s, as does thick as in crass or stupid. Thick, as in that’s a bit thick, meaning excessive or unfair is a British colloquialism and dates from the late 19th century and has obvious connections to Lay it on thick. See also Thick as a plank, Thick and fast.