特に
とくに · tokuni · JLPT N4 · adverb
particularly
特 = special + に (adverb marker): specially, hence particularly
特 is the same character as in 特別 (tokubetsu, special). Adding the particle に turns it into an adverb, just as English adds -ly. So 特に is literally special-ly: singling one thing out above the rest.
特 — cow 牛 + temple 寺 (phonetic)
Originally referred to a male bull or large ox, with 牛 'cow' as the meaning component and 寺 supplying the sound. Over time it shifted from 'bull' to 'special, particular, unique,' the sense used today.