追及
ついきゅう · tsuikyuu · JLPT N1 · noun
probe
追 — 辶 (walk) + 𠂤 (small mound/heap)
Originally a semantic-phonetic compound: 辶 ('walk/movement') gives the meaning of going after something, while 𠂤 supplied the ancient sound. Early bronze inscriptions show it meaning to chase or pursue an enemy. The modern senses — 'pursue,' 'chase after,' 'retroactively' — all extend from this original idea of following in motion.
及 — hand 又 reaching person 人
Originally a pictograph showing a hand (又) catching or reaching a person from behind, depicting the act of catching up to someone. The core meaning 'to reach' or 'to catch up to' extended to 'and' (reaching/including more items) and 'in time for'. Modern form simplifies the person and hand into connected strokes.