Idioms with Body Parts

Every language grows a thick layer of figurative expressions on the parts of the body, and Czech is no exception — the head, the hands, the eyes and the heart all carry meanings far beyond anatomy. Learning these idioms does two jobs at once. First, they are genuinely high-frequency, everyday speech, not museum pieces: a Czech will tell you they have their hands full or that someone crawls up their nerves without a second thought. Second, the paired body parts (ruce, nohy, oči, uši) drag along the special dual-remnant case forms — the fossilized -ma instrumental and the -ou/-í genitive/locative — so an idiom is the most natural place to drill those forms into muscle memory. This page teaches a set of attested idioms in context and shows how their body-part nouns behave.

Head idioms: mít máslo na hlavě and friends

The head (hlava) is where guilt, cleverness, and worry live. The most vivid idiom is mít máslo na hlavě — literally "to have butter on one's head" — meaning to have a guilty conscience, to be the last person entitled to criticize. The image is of butter that melts and drips down and gives you away; you are in no position to point fingers when you have your own mess on your head.

Note that hlava here is singular and behaves as an ordinary hard feminine — na hlavě is a plain locative, přes hlavu a plain accusative. The dual complications start only with the paired parts below.

Hand idioms and the dual instrumental rukama

Hands (ruce) generate a whole cluster of idioms about being busy, being reliable, and things passing along. Three you will hear constantly:

• mít plné ruce práce — "to have hands full of work," i.e. to be swamped.
• dát za někoho ruku do ohně — "to put one's hand in the fire for someone," i.e. to vouch for them absolutely.
• jít z ruky do ruky — "to go from hand to hand," i.e. to change owners rapidly, to be passed around.

Here the singular ruka declines normally (do ruky, do ohně are ordinary genitives). But the moment you reach for the instrumental plural — "with my own hands" — you hit the dual remnant, and both the noun and its modifier take the -ma / -íma ending:

This is the pitfall the brief warns about: an English speaker who has learned the "regular" instrumental plural -ami will regularize the fixed phrase to vlastními rukami — which is simply wrong. For these four body parts, -ma (noun) and -ýma/-íma (modifier) are the codified written standard, not colloquial slang. The full paradigm is on the body-part duals page; the wider story of the -ma instrumental is at the colloquial -ma instrumental.

Eye idioms and the locative v očích

The eyes (oči) carry idioms about first impressions, attraction, and judgement. Two frequent ones:

• padnout někomu do oka — "to fall into someone's eye," i.e. to catch their fancy, to take a liking to.
• být někomu trnem v oku — "to be a thorn in someone's eye," i.e. to be an irritation they wish gone.

Both of these use the singular oko (do oka, v oku), because the idiom conceptualizes "the eye" as a single organ of perception. When you move to the plural — "in someone's eyes," meaning in their estimation or literally welling up — you get the dual -ích locative:

Heart idioms: mluvit od srdce

The heart (srdce, a neuter noun) is the seat of sincerity and courage. Mluvit od srdce — "to speak from the heart" — means to speak sincerely, without calculation. A brave person má srdce na správném místě ("has their heart in the right place"), and something that weighs on you leží na srdci.

Srdce is invariant enough in the singular that it poses no dual trap — it is the paired parts (hands, feet, eyes, ears) that carry the fossilized forms.

Nerve and foot idioms

Two more that round out an everyday repertoire. Lézt někomu na nervy — "to climb on someone's nerves" — is the exact equivalent of English "to get on someone's nerves," and it is extremely common. And být jednou nohou v hrobě — "to be with one foot in the grave" — happens, unusually, to map neatly onto its English twin.

Notice jednou nohou: that is the singular instrumental of noha (with one foot), an ordinary hard-feminine form — no dual involved because it is genuinely one foot. Compare the plural, where the dual kicks in:

That contrast — jednou nohou (singular, ordinary) versus na nohou (plural, dual remnant) — is exactly the kind of thing that trips up learners who assume one form covers both.

Common Mistakes

The instinct to apply the "normal" -ami ending is strong, but ruce, nohy, oči, uši are the four exceptions where -ma is the codified written form. See remnants of the dual.

Padnout do oka is frozen in the singular even though we have two eyes. Pluralizing it, however logical, breaks the idiom.

English body idioms translated word-for-word almost never survive. "Pull someone's leg" is dělat si z někoho legraci — no leg anywhere.

Key Takeaways

• Czech body-part idioms are frequent, everyday speech — mít máslo na hlavě (a guilty conscience), mít plné ruce práce (be swamped), dát ruku do ohně (vouch for), padnout do oka (catch one's fancy), mluvit od srdce (speak sincerely), lézt na nervy (get on one's nerves), být jednou nohou v hrobě (one foot in the grave).
• Do not translate English body idioms literally — they rarely map (tahat za nohu ≠ "pull someone's leg").
• The paired parts ruce, nohy, oči, uši carry the fossilized dual endings: instrumental -ma (rukama, nohama, očima, ušima, with modifiers in -ýma/-íma), genitive/locative -ou/-í (rukou, nohou, očích, uších).
• Idioms fix the number for you: some are singular (do oka, jednou nohou), some plural (v očích, na nohou). Learn each as a whole.