a seed / a pit or stone in a fruit / a gamete (reproductive cell such as a spermatozoan or egg) / a lineage, bloodline / an origin, cause / the materials or ingredients from which something is made

(physics) baryon

physics (as an area of study)

basis, foundation / (martial arts) kihon

physics, the physical aspects of a phenomenon or a system

(geology, physics) geophysics

astrophysics

(physics) theoretical physics

biophysics

nuclear physics