假如
jiǎrú · HSK 4
if
假 = fake/if + 如 = as/like; together 'if it were so'
假 carries the 'suppose/hypothetical' sense (same 假 as 假设 'hypothesize'), and 如 means 'as/like/if'. Stacked, 假如 reads as 'supposing that' — a slightly more formal 'if' than 如果.
假 — person radical 亻 + 叚 (borrow)
假 combines the person radical 亻 with 叚, which originally meant 'to borrow' and provides the sound. The core idea is a person borrowing something, which extended to 'borrowed,' 'not real,' or 'fake.' From there it also developed the meaning 'leave/vacation' (time borrowed away from work).
如 — woman radical 女 + mouth 口
Originally a phono-semantic compound where 女 (woman) suggested compliance and 口 (mouth) indicated speaking or following orders. The early sense was 'to follow' or 'to comply with what is said,' which extended to 'to be like' or 'as if.' Modern uses like 'if' and 'such as' grew from this comparative meaning.