[thick.en] vb thick.ened ; thick.en.ing vt (15c) 1 a: to make thick, dense, or viscous in consistency "~ gravy with flour" b: to make close or compact
2: to increase the depth or diameter of
3: to make inarticulate: blur "alcohol ~ed his speech" ~ vi 1 a: to become dense "the mist ~ed" b: to become concentrated in numbers, mass, or frequency
2: to grow blurred or obscure
3: to grow broader or bulkier
4: to grow complicated or keen "the plot ~s" -- thick.en.er n