by adolescent male, Cadmus. Idiosyncratic? Stroking face of another with fingers and palm is rare and of unknown function. Cf. scratch socially, stroke type. 9. See video. struggle free When pinned down by stronger partner in play, or by group during gang attack, victim exerts maximum effort to get free by push, pull, kick, bite, etc. 3. stumble Lose footing, but rarely trip over stone or stick. See video. See also video slap other. subcutaneous tumor Tumor-like skin swelling of hemispheric shape, approximately size of ping-pong ball, often protruding from lower abdomen of chimpanzee. See video. S 182 support older subgroup See party. subordinate Lower-ranking of two individuals. Cf. dominant. See Fig. 11. suck Suck nipple. Plooijs Suck. Goodalls Suckle. Kanos Suckle for bonobos. See video. suck in