A subset of a (biochemical) pathway / An alternative route in part of a (biochemical) pathway

(anatomy) A natural outgrowth, swelling or enlargement, usually of an organism; a protuberance on a bone. / (botany) The external part of a cone scale. / (geology) A branch of a dike or vein.

(surfing, snowboarding) One who rides with the right foot forward.

Third-person singular simple present indicative form of write down