5a deviation from correct syntax or grammar s_l_c_s_ 9a statistician who calculates insurance risks a_ _ _ _r_ 19a process of foetal development in a viviparous mammals womb g_ _t_ _ _o_ 20d projecting part of a gearwheel comb etc_ _ _t_ 24d twentieth letter of the greek alphabet between tau and phi u_s_l_n